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1.
Ann Bot ; 125(7): 1127-1135, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32185392

RESUMEN

BACKGROUND AND AIMS: Herkogamy, or anther-stigma separation, is known to reduce self-pollen deposition, but little is known about the relative efficacy of different modes or conformations of herkogamy. We assessed the effectiveness of vertical versus lateral herkogamy in preventing or promoting self-pollen deposition in the annual herb Lysimachia arvensis, a plant with lineages that differ in flower colour, and in which flowers first display lateral and then vertical herkogamy. Because mating between the two lineages compromises fitness through the production of low-quality hybrid offspring, we tested the prediction that individuals sampled from sites occupied by both lineages should have flowers that promote autonomous self-pollen deposition and self-fertilization as a result of selection to reduce deleterious reproductive interference. METHODS: We characterized variation in herkogamy within and among 25 pure and mixed populations of L. arvensis in its European range and assessed the effectiveness of lateral versus vertical herkogamy in avoiding self-pollen deposition. RESULTS: Lateral herkogamy was more effective than vertical herkogamy in limiting self-pollen deposition. In the case of vertical herkogamy, only approach herkogamy was effective. Lineages showed consistent differences in herkogamy traits. In general, angles were smaller for blue than red flowers in most populations, and blue flowers showed approach herkogamy, while red flowers showed predominantly reverse herkogamy. In sympatry, the red lineage showed a reduction of both herkogamy traits while for the blue lineage only lateral herkogamy was reduced. CONCLUSIONS: Our results demonstrate that pollen deposition is affected not only by the degree but also the spatial conformation of herkogamy. They also highlight reduced herkogamy as a potential mechanism for promoting reproductive assurance under pollen limitation, as well as for avoiding reproductive interference between genetically divergent lineages.


Asunto(s)
Flores , Primulaceae , Color , Polen , Polinización , Reproducción , Autofecundación
2.
J Neonatal Perinatal Med ; 13(3): 373-380, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31985475

RESUMEN

BACKGROUND: Differences in the susceptibility of preterm infants to develop necrotizing enterocolitis (NEC) implicate potential genetic differences in response to the inflammatory stimuli leading to NEC. Dual specificity phosphatases (DUSPs) are a key suppressor pathway of the mitogen-activated protein kinase (MAPK) pro-inflammatory signaling pathway. We hypothesized that inherited single nucleotide polymorphisms (SNPs) in DUSP genes contribute to NEC susceptibility in premature infants. METHODS: Patients admitted between 2010 and 2015 born at <  32 weeks GA and≤1,500 g BW with stage II+NEC (cases; n = 50) and age, weight-matched controls (n = 38) were included. Blood samples were collected for DNA isolation. Agena Mass Array assay was used to examine 31 SNPs in 9 different DUSP genes. Calculated minor allele frequencies (MAF) for cases and controls were compared using χ2 and logistic regression. RESULTS: The presence of the rs704074 SNP was associated with a 48% decreased risk of developing NEC (OR 0.52; 95% CI 0.27- 1.01, p = 0.04). The odds of surgical NEC decreased by 78% (OR 0.22; 95% CI 0.06- 0.84, p = 0.027) for each copy of rs704074/G allele in patients with NEC. CONCLUSION: In this small single-center pilot study, DUSP-6 SNP (rs704074) was associated with a lower risk of developing NEC and surgical NEC, the most severe form of NEC, in preterm infants.


Asunto(s)
Fosfatasa 6 de Especificidad Dual/genética , Enterocolitis Necrotizante , Enfermedades del Prematuro , Recien Nacido Prematuro/fisiología , Enterocolitis Necrotizante/diagnóstico , Enterocolitis Necrotizante/genética , Enterocolitis Necrotizante/inmunología , Femenino , Microbioma Gastrointestinal/inmunología , Humanos , Recién Nacido , Enfermedades del Prematuro/diagnóstico , Enfermedades del Prematuro/genética , Enfermedades del Prematuro/inmunología , Mucosa Intestinal/inmunología , Sistema de Señalización de MAP Quinasas/genética , Masculino , Polimorfismo de Nucleótido Simple , Estados Unidos/epidemiología
3.
Chem Commun (Camb) ; 54(78): 10974-10976, 2018 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-30209448

RESUMEN

Synthesis of stable irida-binaphthyl and -phenanthryl complexes, the first examples of metallaaromatic biaryl atropisomers, has been achieved. The combination of experimental and theoretical studies revealed that the nature of these systems is comparable to that of well-known 1,1'-binaphthalene both in terms of aromaticity and atropisomerism.

4.
Dalton Trans ; 47(27): 9064-9071, 2018 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-29931013

RESUMEN

A methoxy(alkenyl)carbenerhodium complex [RhCp*Cl{[double bond, length as m-dash]C(OMe)CH[double bond, length as m-dash]CPh2}(PMe3)]PF6 (2) has been synthesized and used as the starting material for the study of the effect of the metal center (Rh vs. Ir) in the formation of new rhodacycle complexes. While η3 and η5 indenylrhodium complexes have been achieved by the C-H bond activation of a phenyl ring, insertion of terminal alkynes into the rhodium-carbene bond led to the first example of the synthesis of rhodafuran complexes through rhoda-1,3,5-hexatriene intermediates. This new method represents an efficient process to obtain metallafuran complexes.

5.
Fungal Syst Evol ; 2: 263-272, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32467890

RESUMEN

Fungal endophytes comprise one of the most ubiquitous groups of plant symbionts. They live asymptomatically within vascular plants, bryophytes and also in close association with algal photobionts inside lichen thalli. While endophytic diversity in land plants has been well studied, their diversity in lichens and bryophytes are poorly understood. Here, we compare the endolichenic and endophytic fungal communities isolated from lichens and bryophytes in the Barton Peninsula, King George Island, Antarctica. A total of 93 fungal isolates were collected from lichens and bryophytes. In order to determine their identities and evolutionary relationships, DNA sequences of the nuclear internal transcribed spacer (ITS), nuclear ribosomal small subunit (nuSSU), nuclear large subunit (nuLSU), and mitochondrial SSU (mtSSU) rDNA were obtained and protein coding markers of the two largest subunit of RNA polymerase II (RPB1 and RPB2) were generated. Multilocus phylogenetic analyses revealed that most of the fungal isolates were distributed in the following six classes in the phylum Ascomycota: Dothideomycetes, Eurotiomycetes, Lecanoromycetes, Leotiomycetes, Pezizomycetes and Sordariomycetes. For the first time we report the presence of subphylum Mortierellomycotina that may belong to an undescribed order in endophytic fungi. Taken together, our results imply that lichens and bryophytes provide similar niches and harbour a selection of these fungi, indicating generalists within the framework of evolutionary adaptation.

6.
Ann Bot ; 120(3): 447-456, 2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-28911017

RESUMEN

Background and aims: The transition from outcrossing to selfing is a repeated pattern in angiosperm diversification and according to general theory this transition should occur quickly and mixed reproductive systems should be infrequent. However, a large proportion of flowering plants have mixed reproductive systems, even showing inbreeding depression. Recently, several theoretical studies have shown that mixed mating systems can be stable, but empirical studies supporting these assumptions are still scarce. Methods: Hypochaeris salzmanniana, an annual species with populations differing in their self-incompatibility expression, was used as a study case to assess the stability of its mixed reproductive system. Here a descriptive study of the pollination environment was combined with measurements of the stability of the self-incompatibility system, outcrossing rate, reproductive assurance and inbreeding depression in four populations for two consecutive years. Key Results: The reproductive system of populations exhibited a geographical pattern: the proportion of plants decreased from west to east. Pollinator environment also varied geographically, being less favourable from west to east. The self-incompatibility expression of some populations changed markedly in only one year. After selfing, progeny was mainly self-compatible, while after outcrossing both self-incompatible and self-compatible plants were produced. In general, both reproductive assurance and high inbreeding depression were found in all populations and years. The lowest values of inbreeding depression were found in 2014 in the easternmost populations, which experienced a marked increase in self-compatibility in 2015. Conclusions: The mixed reproductive system of H. salzmanniana seems to be an evolutionarily stable strategy, with selfing conferring reproductive assurance when pollinator attendance is low, but strongly limited by inbreeding depression. The fact that the highest frequencies of self-compatible plants appeared in the environments most unfavourable to pollination suggests that these plants are selected in these sites, although high rates of inbreeding depression should impede the complete loss of self-incompatibility. In H. salzmanniana, year-to-year changes in the frequency of self-incompatible individuals are directly derived from the balance between reproductive assurance and inbreeding depression.


Asunto(s)
Asteraceae/fisiología , Polinización , Autoincompatibilidad en las Plantas con Flores , Ambiente , Depresión Endogámica , Reproducción
7.
J Environ Radioact ; 166(Pt 2): 390-397, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27681529

RESUMEN

One of the requirements of the recently approved EU-BSS (European Basic Safety Standards Directive, EURATOM, 2013) is the design and implementation of national radon action plans in the member states (Annex XVIII). Such plans require radon surveys. The analysis of indoor radon data is supported by the existing knowledge about geogenic radiation. With this aim, we used the terrestrial gamma dose rate data from the MARNA project. In addition, we considered other criterion regarding the surface of Spain, population, permeability of rocks, uranium and radium contain in soils because currently no data are available related to soil radon gas concentration and permeability in Spain. Given that, a Spanish radon map was produced which will be part of the European Indoor Radon Map and a component of the European Atlas of Natural Radiation. The map indicates geographical areas with high probability of finding high indoor radon concentrations. This information will support legislation regarding prevention of radon entry both in dwellings and workplaces. In addition, the map will serve as a tool for the development of strategies at all levels: individual dwellings, local, regional and national administration.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Radiación de Fondo , Monitoreo de Radiación , Radón/análisis , Rayos gamma , Radio (Elemento)/análisis , España , Encuestas y Cuestionarios , Uranio/análisis
8.
Dalton Trans ; 43(46): 17366-74, 2014 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-25330356

RESUMEN

Iridanaphthalene complexes are synthesized from the corresponding methoxy(alkenyl)carbeneiridium compounds. The electronic character of the substituents on the 6-position of the metallanaphthalene ring is crucial from the point of view of the stability of the iridanaphthalene, [Ir[upper bond 1 start]Cp*{=C(OMe)CH=C(o-C[upper bond 1 end]6H4)(Ph)}(PMe3)]PF6, vs. its transformation to the corresponding indanone derivatives. Stability studies of the iridanaphthalene compounds revealed that strong electron donor substituents (-OMe) stabilize the iridanaphthalene, while weak electron donor (-Me) and electron withdrawing (-NO2) groups favor the formation of indanone derivatives. Two possible indanone isomers can be obtained in the conversion of the unstable iridanaphthalene complexes and a mechanism for the formation of these isomers is proposed.

9.
J Evol Biol ; 27(9): 1965-74, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25056638

RESUMEN

The deceptive Iris lutescens (Iridaceae) shows a heritable and striking flower colour polymorphism, with both yellow- and purple-flowered individuals growing sympatrically. Deceptive species with flower colour polymorphism are mainly described in the family Orchidaceae and rarely found in other families. To explain the maintenance of flower colour polymorphism in I. lutescens, we investigated female reproductive success in natural populations of southern France, at both population and local scales (within populations). Female reproductive success was positively correlated with yellow morph frequency, at both the population scale and the local scale. Therefore, we failed to observe negative frequency-dependent selection (NFDS), a mechanism commonly invoked to explain flower colour polymorphism in deceptive plant species. Flower size and local flower density could also affect female reproductive success in natural populations. Pollinator behaviour could explain the positive effect of the yellow morph, and our results suggest that flower colour polymorphism might not persist in I. lutescens, but alternative explanations not linked to pollinator behaviour are discussed. In particular, NFDS, although an appealingly simple explanation previously demonstrated in orchids, may not always contribute to maintaining flower colour polymorphism, even in deceptive species.


Asunto(s)
Flores , Género Iris/fisiología , Polimorfismo Genético , Francia , Frutas , Aptitud Genética , Genética de Población , Género Iris/genética , Fenotipo , Polinización , Análisis de Componente Principal
10.
Radiat Prot Dosimetry ; 162(1-2): 58-62, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25013034

RESUMEN

Indoor radon mapping still represents a valuable tool for drawing the picture of the exposure of general public due to radon and radon progeny inhalation in a residential context. The information provided by means of a map is useful not only as awareness and strategic element for authorities and policy-makers, but also as a scientific start-up point in the design of epidemiological and other specific studies on exposure to natural radiation. The requirements for a good mapping are related to harmonisation criteria coming from European recommendations, as well as to national/local characteristics and necessities. Around 12,000 indoor radon measurements have been made since the Spanish national radon programme began at the end of the 1980s. A significant proportion of them resulted from the last campaign performed from 2009 to 12. This campaign completed the first version of a map based on a grid 10 × 10 km(2). In this paper, the authors present the main results of a new map together with the criteria adopted to improve the number of measurements and the statistical significance of them.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Contaminación del Aire Interior/análisis , Monitoreo de Radiación , Protección Radiológica , Radón/análisis , Vivienda , Humanos , España
11.
J Radiol Prot ; 33(3): 605-20, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23803560

RESUMEN

Identifying radon-prone areas is key to policies on the control of this environmental carcinogen. In the current paper, we present the methodology followed to delineate radon-prone areas in Spain. It combines information from indoor radon measurements with γ-radiation and geological maps. The advantage of the proposed approach is that it lessens the requirement for a high density of measurements by making use of commonly available information. It can be applied for an initial definition of radon-prone areas in countries committed to introducing a national radon policy or to improving existing radon maps in low population regions.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Monitoreo de Radiación/métodos , Radón/análisis , Contaminación del Aire Interior/prevención & control , Recolección de Datos , Rayos gamma , Mapeo Geográfico , Geología/métodos , Humanos , Modelos Lineales , Monitoreo de Radiación/legislación & jurisprudencia , Radón/efectos adversos , España
12.
Case Rep Hematol ; 2012: 428279, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22937328

RESUMEN

Histiocytic sarcoma (HS) is a neoplasm derived from histiocytes. Its diagnosis was not clear until its immunohistochemistry profile was correctly established. Not much is known about its genetic properties. We report a case of a 48-year-old male patient whose bone marrow was almost completely occupied by monomorphic medium size neoplastic cellularity. Its immunohistochemical profile was CD68(+), CD4(+), CD45(+) with negativity of other dendritic cells, and other lineage markers. Cytogenetic study showed 4 related clones: one with trisomy 8 and extra material on the short arms of chromosome 4; a second line with tetrasomy of chromosome 8, add(4)(p16); the third clone had the same alterations as the previous and deletion of chromosome 3 at q11; the fourth line had tetrasomy 8 and translocation t(3;5)(q25;q35). To our knowledge this is the first HS case showing chromosome 8 trisomy and tetrasomy and the other described alterations.

14.
Plant Dis ; 96(7): 990-996, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30727214

RESUMEN

The effectiveness of a combination of soil solarization and poultry manure (raw or pelletized) amendments for the control of root-knot nematode (Meloidogyne incognita) was tested in carnation (Dianthus caryophyllus) crops grown in in-ground beds under plastic-covered greenhouse conditions in southern Spain. Our trials demonstrated that soil solarization alone did not provide sufficient control of root-knot nematode, because the carnation growing season in this region only partly coincides with the most effective period for solarization, resulting in an insufficient duration of treatment during a key period for effectiveness. Chemical fumigation with 1,3-dichloropropene + chloropicrin prior to planting was effective in reducing nematode population densities in soil. Its effects spanned 9 months after planting, resulting in acceptable crop yields. In comparison, the combination of soil solarization and raw or pelletized poultry manure was slightly less effective than chemical fumigation for control of this pathogen but crop yields after 9 months were similar. However, the higher root gall indices observed after 9 months, in comparison with chemically fumigated plots, indicated the need for a reapplication of the organic manure treatment at the start of each successive growing season.

16.
J Environ Radioact ; 102(11): 995-1007, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21827963

RESUMEN

In the frame of an epidemiological study carried out in the influence areas around the Spanish nuclear facilities (ISCIII-CSN, 2009. Epidemiological Study of The Possible Effect of Ionizing Radiations Deriving from The Operation of Spanish Nuclear Fuel Cycle Facilities on The Health of The Population Living in Their Vicinity. Final report December 2009. Ministerio de Ciencia e Innovación, Instituto de Salud Carlos III, Consejo de Seguridad Nuclear. Madrid. Available from: http://www.csn.es/images/stories/actualidad_datos/especiales/epidemiologico/epidemiological_study.pdf), annual effective doses to public have been assessed by the Spanish Nuclear Safety Council (CSN) for over 45 years using a retrospective realistic-dose methodology. These values are compared with data from natural radiation exposure. For the affected population, natural radiation effective doses are in average 2300 times higher than effective doses due to the operation of nuclear installations (nuclear power stations and fuel cycle facilities). When considering the impact on the whole Spanish population, effective doses attributable to nuclear facilities represent in average 3.5×10(-5)mSv/y, in contrast to 1.6mSv/y from natural radiation or 1.3mSv/y from medical exposures.


Asunto(s)
Exposición a Riesgos Ambientales/análisis , Plantas de Energía Nuclear , Humanos , Dosis de Radiación , Estudios Retrospectivos , Medición de Riesgo/métodos , España
17.
Mol Phylogenet Evol ; 61(3): 659-70, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21864695

RESUMEN

Rumex bucephalophorus is a very polymorphic species that has been subjected to various taxonomic studies in which diverse infraspecific taxa have been recognised on the basis of diaspore traits. In this study we used molecular markers (ITS and AFLP) to explore this remarkable diversity, to test previous hypotheses of classification, and attempt to explain biogeographic patterns. Results show that R. bucephalophorus forms a monophyletic group in which diversification began around 4.2 Mya, at the end of Messinian Salinity Crisis. The two molecular markers clearly show a deep divergence separating subsp. bucephalophorus from all other subspecific taxa, among which subsp. canariensis also constitutes a separate and well distinguishable unit. In contrast, subspecies hispanicus and subsp. gallicus constitute a monophyletic group in which three subgroups can be recognised: subsp. hispanicus, subsp. gallicus var. gallicus and subsp. gallicus var. subaegeus. However, these three subgroups are not clearly distinguished genetically or morphologically, so that in formal classification it would be preferable to treat them at the varietal level.


Asunto(s)
Clasificación , Filogenia , Polimorfismo Genético , Rumex/clasificación , Rumex/genética , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Teorema de Bayes , Núcleo Celular/genética , Análisis por Conglomerados , ADN Intergénico/genética , ADN de Plantas/genética , Genética de Población , Geografía , Datos de Secuencia Molecular , Marruecos , Análisis de Componente Principal , Dispersión de Semillas/genética , España
18.
J Environ Radioact ; 102(1): 1-7, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20952107

RESUMEN

Radioactive and chemical risks coexist in NORM industries although they are usually addressed separately by regulations. The European Union (EU) has developed extensive legislation concerning both matters, which has been diversely reflected in national policies. We consider the case of the Spanish phosphate industry and analyse to which extent regulatory mandates have reduced the historical and ongoing radiological impact on the environment of phosphate facilities. Although no specific radiological constraints on effluent monitoring and release or on waste disposal have yet been imposed on NORM industries in Spain, other environmental regulations have achieved a substantial reduction on the phosphate industry impact. Nevertheless, a more efficient control could be established by eliminating the current conceptual and practical separation of chemical and radioactive risks in NORM industries. We highlight research needs to accomplish so and propose shorter-term measures that require active cooperation among the regulatory bodies involved.


Asunto(s)
Residuos Industriales/análisis , Fosfatos , Monitoreo de Radiación , Residuos Radiactivos/análisis , Monitoreo de Radiación/legislación & jurisprudencia , España
19.
Avian Dis ; 53(1): 115-8, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19432013

RESUMEN

In the present study, the hemagglutinating activity of seven reference strains, and nine Mexican and three Danish field isolates, of Gallibacterium was investigated by using fresh erythrocytes of 19 different types including chicken (broiler, rooster, layer hen), turkey, pigeon, quail, duck, Harris's hawk (Parabuteo unicinctus), house finch (Carpodacus mexicanus), cow, sheep, horse, dog, rabbit, pig, and human (groups A, B, AB, and O; Rh+). Agglutination was observed for broiler chicken, layer hen, quail, rabbit, and pig erythrocytes with a subset of Gallibacterium strains, whereas most tested strains agglutinated rabbit erythrocytes. Transmission electron microscopic examination of a hemagglutinating strain demonstrated a close interaction between the bacterial and erythrocyte surfaces. The results indicate that some Gallibacterium strains are able to agglutinate avian or mammalian erythrocytes, or both. However, the mechanisms enabling hemagglutination are not known and will be addressed in future studies.


Asunto(s)
Hemaglutinación/fisiología , Pasteurellaceae/clasificación , Pasteurellaceae/fisiología , Animales , Eritrocitos/fisiología , Humanos
20.
Appl Radiat Isot ; 66(11): 1567-71, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18508275

RESUMEN

Residues from industrial activities involving naturally occurring radioactive materials (NORMs) may cause radiation exposures to members of the public, particularly when NORM-affected land is brought into residential use. To provide an adequate protection against radiation in such situations, the following limiting criteria are currently required in Spain for releasing NORM-affected land: (i) no more than a 300 microSv yr(-1) increase (excluding radon doses) over the natural background; (ii) (222)Rn concentrations in hypothetical future dwellings lower than 200 Bq m(-3); and (iii) reduction of all radiation exposures to as low as reasonable achievable. This paper addresses some of the problems encountered in translating the (222)Rn criterion into site-specific release limits and in demonstrating compliance with them.


Asunto(s)
Radiación de Fondo , Exposición a Riesgos Ambientales/análisis , Adhesión a Directriz/organización & administración , Guías como Asunto , Monitoreo de Radiación/normas , Protección Radiológica/normas , Residuos Radiactivos/análisis , Contaminantes Radiactivos del Suelo/análisis , Carga Corporal (Radioterapia) , Predicción , Regulación Gubernamental , Internacionalidad , Monitoreo de Radiación/legislación & jurisprudencia , Protección Radiológica/legislación & jurisprudencia , Residuos Radiactivos/prevención & control , Radioisótopos/análisis , Estándares de Referencia , Medición de Riesgo/legislación & jurisprudencia , Medición de Riesgo/normas , Medición de Riesgo/tendencias , Administración de la Seguridad/legislación & jurisprudencia , Administración de la Seguridad/normas , Administración de la Seguridad/tendencias , España
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