62 research outputs found
Un modelo de potencialidad climática para la trufa negra (Tuber melanosporum) en Teruel (España)
Black truffle (Tuber melanosporum) is an edible ectomycorrhizal mushroom whose cultivation is an economically-viable alternative in rural areas affected by depopulation. In the province of Teruel (Spain), truffle plantations occupy nowadays more than 4,500 ha, but no land use planning guidelines have been available. Species distribution models are tools that allow managers, farmers and foresters to plan ahead and make decisions with a scientific basis. The territory climatically suitable for T. melanosporum in Teruel has been predicted using a method based on the ecology field theory, previously tested in the development of distribution models for forest species. A dataset of 924 locations where black truffle has been collected in the Catalano-Aragonesa ecoregion and eight climatic parameters deeply influencing the presence and fructification of the black truffle have been considered and their corresponding habitats have been built. The distribution model, corrected under lithological criteria, has identified more than 8,000 km² as suitable for black truffle fructification in Teruel, almost 55% of the province, belonging 3,000 of them to the optimal class. This land is mainly distributed over the regions of Gúdar-Javalambre, Comunidad de Teruel and Maestrazgo. A further correction based on land-use criteria has identified more than 4,000 km² as suitable for truffle plantations, being 1,150 of them optimal. The model here presented will help to a proper planning for truffle cultivation in the province of Teruel.La trufa negra (Tuber melanosporum) es un hongo ectomicorrícico comestible cuyo cultivo supone en la actualidad una alternativa económica viable para zonas rurales afectadas gravemente por la despoblación. En la provincia de Teruel (España) hay más de 4.500 ha de plantaciones truferas, instaladas sin ningún proceso de planificación orientado a alcanzar un territorio rural ordenado. Los modelos territoriales de potencialidad o aptitud para las especies son herramientas que permiten a los gestores, agricultores y selvicultores desarrollar dicha planificación y tomar decisiones fundamentadas en un conocimiento científico lo más riguroso posible.
Utilizando un método basado en la teoría de campos aplicada a la ecología, habitual para elaborar las áreas potenciales de especies forestales vegetales, se ha determinado el territorio climáticamente apto para T. melanosporum en la provincia Teruel. Para construir este modelo se han utilizado 924 localizaciones de la ecorregión Catalano-Aragonesa. Elaborando ocho parámetros climáticos trascendentes para la fructificación de la trufa negra, se han construido sus correspondientes hábitats.
El modelo de potencialidad climática elaborado, completado con una corrección litológica, ha permitido identificar algo más de 8.000 km2 como aptos para la recolección de la trufa negra en Teruel, casi el 55% de la provincia, de los cuales 3.000 corresponden a la clase óptima y están distribuidos por las comarcas de Gúdar-Javalambre, Comunidad de Teruel y Maestrazgo. La adaptación del modelo ha permitido identificar más de 4.000 km2 como aptos para la instalación de plantaciones truferas, 1.150 de los cuales tienen potencialidad óptima.
El modelo generado en el presente trabajo permitirá la adecuada planificación territorial de la truficultura en la provincia de Teruel
The correlation between urinary 5-hydroxyindoleacetic acid and sperm quality in infertile men and rotating shift workers
<p>Abstract</p> <p>Background</p> <p>Serotonin is a neurotransmitter that modulates a wide range of neuroendocrine functions. However, excessive circulating serotonin levels may induce harmful effects in the male reproductive system. The objective of this study was to evaluate whether the levels of urinary 5-hydroxyindoleacetic acid (5-HIIA), a major serotonin metabolite, correlate with different classical seminal parameters.</p> <p>Methods</p> <p>Human ejaculates were obtained from 40 men attending infertility counselling and rotating shift workers by masturbation after 4-5 days of abstinence. Urinary 5- HIIA concentration was quantified by using a commercial ELISA kit. Forward motility was assessed by a computer-aided semen analysis (CASA) system. Sperm concentration was determined using the haemocytometer method. Sperm morphology was evaluated after Diff-Quik staining, while sperm vitality was estimated after Eosin-Nigrosin vital staining.</p> <p>Results</p> <p>Our results show that urinary 5-HIIA levels obtained from a set of 20 volunteers negatively correlated with sperm concentration, forward motility, morphology normal range and sperm vitality. On the other hand, we checked the relationship between male infertility and urinary 5-HIIA levels in 20 night shift workers. Thus, urinary 5-HIIA levels obtained from 10 recently-proven fathers were significantly lower than those found in 10 infertile males. Additionally, samples from recent fathers exhibited higher sperm concentration, as well as better forward motility and normal morphology rate.</p> <p>Conclusions</p> <p>In the light of our findings, we concluded that high serotonin levels, indirectly measured as urinary 5-HIIA levels, appear to play a role as an infertility determinant in male subjects.</p
Gene expression profiling of mouse p53-deficient epidermal carcinoma defines molecular determinants of human cancer malignancy
<p>Abstract</p> <p>Background</p> <p>The epidermal specific ablation of <it>Trp53 </it>gene leads to the spontaneous development of aggressive tumors in mice through a process that is accelerated by the simultaneous ablation of <it>Rb </it>gene. Since alterations of p53-dependent pathway are common hallmarks of aggressive, poor prognostic human cancers, these mouse models can recapitulate the molecular features of some of these human malignancies.</p> <p>Results</p> <p>To evaluate this possibility, gene expression microarray analysis was performed in mouse samples. The mouse tumors display increased expression of cell cycle and chromosomal instability associated genes. Remarkably, they are also enriched in human embryonic stem cell gene signatures, a characteristic feature of human aggressive tumors. Using cross-species comparison and meta-analytical approaches, we also observed that spontaneous mouse tumors display robust similarities with gene expression profiles of human tumors bearing mutated TP53, or displaying poor prognostic outcome, from multiple body tissues. We have obtained a 20-gene signature whose genes are overexpressed in mouse tumors and can identify human tumors with poor outcome from breast cancer, astrocytoma and multiple myeloma. This signature was consistently overexpressed in additional mouse tumors using microarray analysis. Two of the genes of this signature, AURKA and UBE2C, were validated in human breast and cervical cancer as potential biomarkers of malignancy.</p> <p>Conclusions</p> <p>Our analyses demonstrate that these mouse models are promising preclinical tools aimed to search for malignancy biomarkers and to test targeted therapies of prospective use in human aggressive tumors and/or with p53 mutation or inactivation.</p
Reduced levels of intracellular calcium releasing in spermatozoa from asthenozoospermic patients
<p>Abstract</p> <p>Background</p> <p>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.</p> <p>Methods</p> <p>Human ejaculates were obtained from healthy volunteers and asthenospermic men by masturbation after 4–5 days of abstinence. For determination of cytosolic free calcium concentration, spermatozoa were loaded with the fluorescent ratiometric calcium indicator Fura-2.</p> <p>Results</p> <p>Treatment of spermatozoa from normospermic men with 20 micromolar progesterone plus 1 micromolar thapsigargin in a calcium free medium induced a typical transient increase in cytosolic free calcium concentration due to calcium release from internal stores. Similar results were obtained when spermatozoa were stimulated with progesterone alone. Subsequent addition of calcium to the external medium evoked a sustained elevation in cytosolic free calcium concentration indicative of capacitative calcium entry. However, when progesterone plus thapsigargin were administered to spermatozoa from patients with asthenozoospermia, calcium signal and subsequent calcium entry was much smaller compared to normospermic patients. As expected, pretreatment of normospermic spermatozoa with both the anti-progesterone receptor c262 antibody and with progesterone receptor antagonist RU-38486 decreased the calcium release induced by progesterone. Treatment of spermatozoa with cytochalasin D or jasplakinolide decreased the calcium entry evoked by depletion of internal calcium stores in normospermic patients, whereas these treatments proved to be ineffective at modifying the calcium entry in patients with asthenozoospermia.</p> <p>Conclusion</p> <p>Our results suggest that spermatozoa from asthenozoospermic patients present a reduced responsiveness to progesterone.</p
Polymorphisms of CD16A and CD32 Fcγ receptors and circulating immune complexes in Ménière's disease: a case-control study
<p>Abstract</p> <p>Background</p> <p>Autoimmune diseases with elevated circulating autoantibodies drive tissue damage and the onset of disease. The Fcγ receptors bind IgG subtypes modulating the clearance of circulating immune complexes (CIC). The inner ear damage in Ménière's disease (MD) could be mediated by an immune response driven by CIC. We examined single-nucleotide polymorphism (SNPs) in the CD16A and CD32 genes in patients with MD which may determine a Fcγ receptor with lower binding to CIC.</p> <p>Methods</p> <p>The functional CD16A (FcγRIIIa*559A > C, rs396991) and CD32A (FcγRIIa*519A > G, rs1801274) SNPs were analyzed using PCR-based TaqMan Genotyping Assay in two cohorts of 156 mediterranean and 112 Galicia patients in a case-control study. Data were analyzed by χ<sup>2 </sup>with Fisher's exact test and Cochran-Armitage trend test (CATT). CIC were measured by ELISA for C1q-binding CIC.</p> <p>Results</p> <p>Elevated CIC were found in 7% of patients with MD during the intercrisis period. No differences were found in the allelic frequency for rs396991 or rs1801274 in controls subjects when they were compared with patients with MD from the same geographic area. However, the frequency of AA and AC genotypes of CD16A (rs396991) differed among mediterranean and Galicia controls (Fisher's test, corrected p = 6.9 × 10<sup>-4 </sup>for AA; corrected p = 0.02 for AC). Although genotype AC of the CD16A receptor was significantly more frequent in mediterranean controls than in patients, [Fisher's test corrected p = 0.02; OR = 0.63 (0.44-0.91)], a genetic additive effect for the allele C was not observed (CATT, p = 0.23). Moreover, no differences were found in genotype frequencies for rs396991 between patients with MD and controls from Galicia (CATT, p = 0.14). The allelic frequency of CD32 (rs1801274) was not different between patients and controls either in mediterranean (p = 0.51) or Galicia population (p = 0.11).</p> <p>Conclusions</p> <p>Elevated CIC are not found in most of patients with MD. Functional polymorphisms of CD16A and CD32 genes are not associated with onset of MD.</p
A Functional Role of RB-Dependent Pathway in the Control of Quiescence in Adult Epidermal Stem Cells Revealed by Genomic Profiling
Continuous cell renewal in mouse epidermis is at the expense of a pool of pluripotent cells that lie in a well defined niche in the hair follicle known as the bulge. To identify mechanisms controlling hair follicle stem cell homeostasis, we developed a strategy to isolate adult bulge stem cells in mice and to define their transcriptional profile. We observed that a large number of transcripts are underexpressed in hair follicle stem cells when compared to non-stem cells. Importantly, the majority of these downregulated genes are involved in cell cycle. Using bioinformatics tools, we identified the E2F transcription factor family as a potential element involved in the regulation of these transcripts. To determine their functional role, we used engineered mice lacking Rb gene in epidermis, which showed increased expression of most E2F family members and increased E2F transcriptional activity. Experiments designed to analyze epidermal stem cell functionality (i.e.: hair regrowth and wound healing) imply a role of the Rb-E2F axis in the control of stem cell quiescence in epidermis
Estudio de los Ecosistemas Marinos Vulnerables en aguas internacionales del Atlántico Sudoccidental
En este libro, basado en la mejor información científica disponible hasta la fecha, se presentan los resultados y conclusiones de una serie de trece campañas de investigación multidisciplinar realizadas entre octubre de 2007 y abril de 2010 por los componentes del Grupo ATLANTIS a bordo del B/O MIGUEL OLIVER, propiedad de la Secretaría General de Pesca (SGP).
El estudio surge a raíz de la solicitud por parte de la SGP (anteriormente denominada Secretaría General del Mar) al Instituto Español de Oceanografía (IEO), para la realización de una serie de campañas de investigación multidisciplinar en aguas internacionales del Atlántico Sudoccidental, dirigidas al estudio de los Ecosistemas Marinos Vulnerables (EMVs) y de las posibles interacciones con las actividades pesqueras.
El objetivo final de dichas campañas era el estudio y la identificación cuantitativa, cualitativa y geográfica de los EMVs y de los grupos taxonómicos de organismos sensibles que pudieran existir en la zona de estudio, incluyendo la propuesta de posibles zonas marinas a proteger, para una explotación sostenible de los recursos pesqueros en el ámbito del respeto a los EMVs.
Los resultados que se presentan en este libro comprenden los obtenidos a través de los trabajos de geología, geomorfología, bentos, pesca, oceanografía física y análisis de contaminantes en la zona de aguas internacionales del Atlántico Sudoccidental comprendida entre los paralelos 42º y 48ºS, y la isobata de los 1500 m de profundidad (Figura 2.2). Entre estos resultados se incluye el cartografiado y una batimetría detallada de la zona, la descripción del substrato geológico y de los aspectos bentónicos, el análisis de la distribución y abundancia de las especies de mayor interés comercial, la huella de la pesquería, la identificación y descripción preliminar de los EMVs, y la propuesta de Zonas de Protección, basada en criterios Geológicos, Geomorfológicos y Biológicos.
Toda esta información ha sido incorporada para su tratamiento en una plataforma SIG (Sistema de Información Geográfica) y los resultados obtenidos y presentados en este libro vienen acompañados de abundante información gráfica, como imágenes batimétricas en 3D, fotografías de bentos (infauna y epifauna), imágenes tomadas con un ROV (Remotely Operated Vehicle) y con una cámara digital submarina, así como una serie de mapas de distribución, capturas y densidad de las principales especies de interés pesquero. Se incluye también un mapa con la huella de la pesquería (1989-2010) que permita observar la incidencia de las Zonas de Protección propuestas en el área en la que faena habitualmente la flota española de arrastre de fondo.
Como información adicional a la obtenida en las trece campañas de investigación, también se ha utilizado la base de datos creada con la información recogida por el Programa de Observadores del IEO entre los años 1989-2010, referente a datos comerciales, biológicos, oceanográficos y físicos (batimetría, temperatura superficial del mar y temperatura del fondo).
Entre octubre de 2007 y abril de 2010 se han realizado un total de trece campañas de investigación multidisciplinar, que se han concretado en los siguientes trabajos:
• 347 días efectivos de mar
• Prospección de una superficie total de 59.105 km2
• Realización de un total de 91.905 km de perfiles geofísicos
• 102 muestreos con draga de roca
• 209 muestreos con draga box corer
• 519 estaciones de CTD
• 413 lances de pesca
• 413 muestras de sedimentos con el colector de red
• Recogida de varios miles de lotes de muestras de bentos que representan varios centenares de miles de especímenes y/o colonias
• Realización de miles de fotografías de especies bentónicas, centenares de imágenes digitales de alta resolución y decenas de horas de vídeo realizadas con el ROV del barco
Entre los principales resultados de los trabajos de investigación multidisciplinar presentados en este libro hay que destacar la identificación, descripción y delimitación de los EMVs, siguiendo criterios biológicos, geológicos y mixtos; la identificación de los principales grupos bentónicos indicadores de EMVs; la determinación de los valores que representan una captura significativa de los distintos taxones considerados como vulnerables según criterios de la ONU y OSPAR, y finalmente, la propuesta de áreas marinas que deberían ser consideradas como candidatas a ser protegidas.
En total se proponen nueve polígonos de diferente superficie para su valoración como zonas de protección (Figura 7.5) y se hace referencia a la incidencia que el cierre de dichas zonas podría tener sobre la actividad de la flota, es decir, el grado de solapamiento entre las zonas de protección y la huella de la pesquería (Figura 7.6).
Todos estos resultados se presentan acompañados de abundantes gráficas, figuras y mapas.Instituto Español de OceanografíaVersión del edito
The Politics of (and Behind) the UNFCCC’s Loss and Damage Mechanism
Despite being one of the most controversial issues to be recently treated within climate negotiations, Loss and Damage (L&D) has attracted little attention among scholars of International Relations (IR). In this chapter we take the “structuralist paradox” in L&D negotiations as our starting point, considering how IR theories can help to explain the somewhat surprising capacity of weak parties to achieve results while negotiating with stronger parties. We adopt a multi-faceted notion of power, drawing from the neorealist, liberal and constructivist schools of thought, in order to explain how L&D milestones were reached. Our analysis shows that the IR discipline can greatly contribute to the debate, not only by enhancing understanding of the negotiation process and related outcomes but also by offering insights on how the issue could be fruitfully moved forward. In particular, we note the key importance that discursive power had in the attainment of L&D milestones: Framing L&D in ethical and legal terms appealed to standards relevant beyond the UNFCCC context, including basic moral norms linked to island states’ narratives of survival and the reference to international customary law. These broader standards are in principle recognised by both contending parties and this broader framing of L&D has helped to prove the need for action on L&D. However, we find that a change of narrative may be needed to avoid turning the issue into a win-lose negotiation game. Instead, a stronger emphasis on mutual gains through adaptation and action on L&D for both developed and developing countries is needed as well as clarity on the limits of these strategies. Examples of such mutual gains are more resilient global supply chains, reduction of climate-induced migration and enhanced security. As a result, acting on L&D would not feel as a unilateral concession developed countries make to vulnerable ones: it would rather be about elaborating patterns of collective action on an issue of common concern
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