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1.
Semergen ; 50(8): 102283, 2024 Jun 26.
Artigo em Espanhol | MEDLINE | ID: mdl-38936098

RESUMO

OBJECTIVE: The main aim of our study is to know the sociodemographic, clinical, analytical, and functional variables that predict the probability of developing dementia in patients with delirium who attend the emergency room. METHOD: All patients with delirium (n=45) from the emergency room who were admitted to the Geriatrics service of the General University Hospital of Ciudad Real (HGUCR) in 2016-2018 and met the inclusion and exclusion criteria were included. Subsequently, we ran a bivariate and multivariate analysis of the variables that predicted a diagnosis of dementia at six months and a discriminant analysis. RESULTS: 15.6% of patients presented dementia at six months of follow-up, 22.2% had developed cognitive impairment. We conducted a multivariate model (R2 Nagelkerke 0.459) for the probability of developing dementia, with elevated heart rate being the most crucial variable (OR=11.5). The model could excluded dementia with 100% accuracy. Finally, we achieved a discriminant function capable of correctly classifying 95.6% of the cases. It included the following variables of influence: pH, Lawton Brody index, calcium, urea, and heart rate. CONCLUSIONS: A few clinical and analytical variables that are easily detectable in the emergency room, especially tachycardia, could help us better identify those patients with delirium at higher risk of developing dementia, as well as formulate hypotheses about the variables involved in the development of dementia in patients with delirium.

2.
J Phys Condens Matter ; 30(36): 365502, 2018 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-30051888

RESUMO

We characterize the confinement of massless Dirac electrons under axially symmetric magnetic fields in graphene, including zero energy modes and higher energy levels. In particular, we analyze in detail the Aharonov-Casher theorem, on the existence of zero modes produced by magnetic fields with finite flux in two dimensions. We apply techniques of supersymmetric quantum mechanics to determine the confined states by means of the quantum number j associated to isospin and angular momentum. We focus on magnetic fields, regular at the origin, whose asymptotic behaviour is [Formula: see text], with α a real number. A confinement of infinite zero-energy modes and excited states is possible as long as [Formula: see text]. When [Formula: see text] the quantum dot is able to trap an infinite number of zero modes but no excited states, while for [Formula: see text] only a finite number of zero modes are confined.

4.
J Phys Condens Matter ; 27(28): 285501, 2015 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-26102328

RESUMO

The aim of this article was to study the degeneracy of the energy spectrum in a nanotube under a transverse magnetic field. The massless Dirac-Weyl equation has been used to describe the low energy states of this system. The particular case of a singular magnetic field approximated by Dirac delta distributions is considered. It is shown that, under general symmetry conditions, there is a double degeneracy corresponding to periodic solutions with null axial momentum k(z)=0. Also, there may be a kind of sporadic degeneracy for non-vanishing values of k(z), which are explicitly computed in the present example. The proof of these properties is obtained by means of the supersymmetric structure of the Dirac-Weyl Hamiltonian.

5.
J Phys Condens Matter ; 25(16): 165301, 2013 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-23553418

RESUMO

Methods of supersymmetric quantum mechanics are used to obtain analytical solutions for massless Dirac electrons in spherical molecules, including fullerenes, in the presence of magnetic fields. The solutions for Dirac massive charges are also obtained via the solutions of the Dirac-Weyl equation.

6.
Rev Esp Med Nucl Imagen Mol ; 31(5): 249-56, 2012 Sep.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-23067526

RESUMO

OBJECTIVE: To evaluate the efficacy of (18)F-FDG PET-CT in the diagnosis of recurrence of colorectal cancer (CRC) in patients with elevated values of carcinoembryonic antigen (CEA) and/or signs of recurrence in the multidetector CT (MDCT), and to demonstrate that good results can be obtained applying the ALARA principles. MATERIAL AND METHODS: A retrospective study of 54 patients with suspected CRC, who underwent an (18)F-FDG PET-CT, administering a mean dose of 222 MBq (6 mCi) of (18)F-FDG, from 07/2007 to 01/2011 was carried out. Seven patients were excluded, thus studying 47 (27 males, 20 females, mean age 63 years). Recurrence was confirmed by histopathology study in 14 cases and by clinical evolution in 33. The patients were divided into 4 groups. A: patients with elevation of CEA and suspected recurrence in the MDCT. B: elevation of CEA, without suspicious lesions in the MDCT. C: normal levels of CEA and positive MDCT. D: normal levels of CEA and uncertain MDCT. RESULTS: We found sensitivity, specificity, PPV, NPV and overall accuracy of 91%, 69%, 89%, 75% and 85% respectively. For group A, we found 100% sensitivity, in group B, 75% sensitivity with 100% specificity%, for C, sensitivity was 89% with 71% specificity. Finally, in group D, sensitivity was 100% and specificity 60%, respectively. CONCLUSION: Applying a low dose, the (18)F-FDG PET-CT has high diagnostic performance in patients with suspicion of CRC, approaching in a higher grade the ALARA criteria.


Assuntos
Adenocarcinoma/secundário , Neoplasias Colorretais/diagnóstico por imagem , Fluordesoxiglucose F18 , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X , Adenocarcinoma/sangue , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/terapia , Idoso , Biomarcadores Tumorais/sangue , Neoplasias Encefálicas/sangue , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/secundário , Antígeno Carcinoembrionário/sangue , Quimiorradioterapia , Neoplasias Colorretais/sangue , Neoplasias Colorretais/terapia , Terapia Combinada , Feminino , Fluordesoxiglucose F18/administração & dosagem , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Compostos Radiofarmacêuticos/administração & dosagem , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada Espiral
7.
Mol Ecol Resour ; 12(4): 779-81, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22642264

RESUMO

This article documents the addition of 171 microsatellite marker loci and 27 pairs of single nucleotide polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Bombus pauloensis, Cephalorhynchus heavisidii, Cercospora sojina, Harpyhaliaetus coronatus, Hordeum vulgare, Lachnolaimus maximus, Oceanodroma monteiroi, Puccinia striiformis f. sp. tritici, Rhea americana, Salmo salar, Salmo trutta, Schistocephalus solidus, Sousa plumbea and Tursiops aduncus. These loci were cross-tested on the following species: Aquila heliaca, Bulweria bulwerii, Buteo buteo, Buteo swainsoni, Falco rusticolus, Haliaeetus albicilla, Halobaena caerulea, Hieraaetus fasciatus, Oceanodroma castro, Puccinia graminis f. sp. Tritici, Puccinia triticina, Rhea pennata and Schistocephalus pungitii. This article also documents the addition of 27 sequencing primer pairs for Puffinus baroli and Bulweria bulwerii and cross-testing of these loci in Oceanodroma castro, Pelagodroma marina, Pelecanoides georgicus, Pelecanoides urinatrix, Thalassarche chrysostoma and Thalassarche melanophrys.


Assuntos
Bases de Dados Genéticas , Repetições de Microssatélites , Polimorfismo de Nucleotídeo Único , Ecologia , Marcadores Genéticos
8.
Rev Esp Enferm Dig ; 102(9): 542-52, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20883071

RESUMO

Hepatitis B virus (HBV) reactivation results from increased viral replication in inactive carriers or patients with prior infection with HBV. Reactivation may occur spontaneously or secondary to immunomodulating or immunosuppressive chemotherapy. Reactivation may manifest with no symptoms but on occasion results in acute or even severe acute hepatitis. Prevention is the best management approach, hence HBV screening using serology should be performed for all patients undergoing any immunomodulating, immunosuppressive or chemotherapeutic treatment. Antiviral prophylaxis has proven effective in inactive carriers and in some patients with former infection with HBV undergoing selected immunosuppressive therapies.


Assuntos
Hepatite B/etiologia , Hepatite B/terapia , Algoritmos , Terapia Biológica , Hepatite B/prevenção & controle , Humanos , Recidiva , Fatores de Risco
9.
Rev. esp. enferm. dig ; 102(9): 542-552, sept. 2010. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-81568

RESUMO

La reactivación del virus de la hepatitis B se debe a un aumento de la replicación del virus en pacientes portadores inactivos o con infecciones pasadas de VHB. La reactivación puede producirse espontáneamente o de manera secundaria a tratamientos de quimioterapia, inmunomoduladores o inmunosupresores. La reactivación puede manifestarse de manera asintomática pero en algunos casos puede causar hepatitis agudas e incluso hepatitis agudas graves. El mejor tratamiento es la prevención por lo que se debe realizar un cribado del VHB mediante una serología a todos los pacientes que vayan a someterse a cualquier tratamiento inmunomodulador, de quimioterapia o inmunosupresor. El tratamiento profiláctico antiviral ha demostrado ser eficaz en los pacientes portadores inactivos y en algunos pacientes con infecciones pasadas de VHB sometidos a ciertos tratamientos inmunosupresores(AU)


Assuntos
Humanos , Masculino , Feminino , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Anticorpos Anti-Hepatite B/uso terapêutico , Antígenos da Hepatite B , Imunossupressores/uso terapêutico , Vírus da Hepatite B/isolamento & purificação , Fatores de Risco , Ciclofosfamida/uso terapêutico , Vincristina/uso terapêutico , Vírus da Hepatite B , Vírus da Hepatite B/patogenicidade , Indicadores de Morbimortalidade , Programas de Rastreamento/métodos , Antibióticos Antineoplásicos/efeitos adversos , Antineoplásicos/efeitos adversos , Estudos Prospectivos , Estudos Retrospectivos , Doxorrubicina/uso terapêutico
10.
J Comp Pathol ; 142(1): 43-50, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19691968

RESUMO

Wild deer have an important role in the epidemiology of bovine tuberculosis (bTB). The aims of this study were (1) to compare the pattern of lesions present in wild red (Cervus elaphus) and fallow (Dama dama) deer that were naturally infected with Mycobacterium bovis, and (2) to use this information to develop a sampling strategy for the isolation of M. bovis from the lymphoid tissues of the head of these animals. Culture of head lymphoid tissues demonstrated that 28 of 95 red deer and 22 of 100 fallow deer sampled were infected with M. bovis. Approximately 30% of each deer population had no gross lesions. Fallow deer were significantly more likely to have thoracic lesions than red deer. Lesions were observed in the retropharyngeal lymph nodes of 64% of the culture-positive red deer and 43% of the culture positive fallow deer. One third of the red deer, but none of the fallow deer, had well-encapsulated abscess lesions. There were no microscopical differences in the lesions in the lymph nodes of the red and fallow deer. Bacteriological culture from both the tonsil and retropharyngeal lymph nodes increased the rate of isolation of M. bovis by 22% over culture of the retropharyngeal lymph nodes alone in both species. These findings indicate that investigation of wild deer for bTB-compatible lesions should include examination of the medial retropharyngeal, left tracheobronchial, mediastinal, mesenteric and ileocaecal lymph nodes. Sampling for bacteriological culture from head lymphoid tissues should be from the tonsil and the medial retropharyngeal lymph nodes. These protocols may prove useful in bTB surveillance and control in regions where wild deer contribute to the circulation of M. bovis.


Assuntos
Linfonodos/microbiologia , Linfonodos/patologia , Tuberculose/diagnóstico , Tuberculose/veterinária , Animais , Cervos , Mycobacterium bovis/isolamento & purificação , Tonsila Palatina/microbiologia , Tonsila Palatina/patologia , Faringe/microbiologia , Faringe/patologia , Tuberculose/microbiologia
12.
Artigo em Inglês | MEDLINE | ID: mdl-20128428

RESUMO

The date palm (Phoenix dactylifera) has a wide geographical distribution (Middle East, Mediterranean, central Africa, western Asia, Australia, and North America). Pho d 2, the major allergen of date palm pollen was recently identified as a profilin, yet little is known about the nature of the other pollen allergens from this tree. The objective of this study was to characterize clinically significant allergens other than profilins from P. dactylifera pollen using immunoproteomics. In order to reveal the proteins causing the allergy, we used serum from a patient monosensitized to date palm pollen extract who experienced asthma and rhinoconjunctivitis during the palm tree pollen season. The results revealed 2 novel immunoglobulin E-binding proteins not related to the cross-reactive allergen profilin. Individualized allergens of Pdactylifera that cause specific date palm pollen sensitization must be defined to determine the real prevalence of sensitization to this species.


Assuntos
Antígenos de Plantas/imunologia , Asma/diagnóstico , Rinite Alérgica Sazonal/diagnóstico , Adulto , Alérgenos/imunologia , Antígenos de Plantas/sangue , Antígenos de Plantas/genética , Antígenos de Plantas/isolamento & purificação , Asma/complicações , Asma/imunologia , Asma/fisiopatologia , Conjuntivite , Eletroforese em Gel Bidimensional , Feminino , Frutas/imunologia , Galactosidases/genética , Glucosiltransferases/genética , Humanos , Imunização , Proteômica , Rinite , Rinite Alérgica Sazonal/complicações , Rinite Alérgica Sazonal/imunologia , Rinite Alérgica Sazonal/fisiopatologia
13.
Heredity (Edinb) ; 102(2): 190-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18854856

RESUMO

Population fragmentation is a widespread phenomenon usually associated with human activity. As a result of habitat transformation, the philopatric and steppe-specialist Lesser Kestrel Falco naumanni underwent a severe population decline during the last century that increased population fragmentation throughout its breeding range. In contrast, the ubiquitous Eurasian Kestrel Falco tinnunculus did not suffer such adverse effects, its breeding range still remaining rather continuous. Using microsatellites, we tested the effects of population fragmentation on large-scale spatial patterns of genetic differentiation and diversity by comparing these two sympatric and phylogenetically related species. Our results suggest that habitat fragmentation has increased genetic differentiation between Lesser Kestrel populations, following an isolation-by-distance pattern, while the population of Eurasian Kestrels is panmictic. Contrary to expectations, we did not detect significant evidence of reduced genetic variation or increased inbreeding in Lesser Kestrels. Although this study reports genetic differentiation in a species that has potential for long-distance dispersal but philopatry-limited gene flow, large enough effective population sizes and migration may have been sufficient to mitigate genetic depauperation. A serious reduction of genetic diversity in Lesser Kestrels would, therefore, only be expected after severe population bottlenecks following extreme geographic isolation.


Assuntos
Migração Animal , Falconiformes/genética , Grupos de População Animal/genética , Animais , Cruzamento , Variação Genética , Repetições de Microssatélites , Dinâmica Populacional
14.
J Phys Condens Matter ; 21(45): 455305, 2009 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-21694010

RESUMO

Exact analytical solutions for the bound states of a graphene Dirac electron in various magnetic fields with translational symmetry are obtained. In order to solve the time-independent Dirac-Weyl equation the factorization method used in supersymmetric quantum mechanics is adapted to this problem. The behavior of the discrete spectrum, probability and current densities are discussed.

15.
Comp Biochem Physiol B Biochem Mol Biol ; 150(2): 147-52, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18378172

RESUMO

Red hues are a challenge in studies on the evolution of bird coloration, as multiple pigments such as carotenoids, pheomelanin, psittacofulvins, porphyrins, turacin, haemoglobin and even exogenous iron-oxides, may confer red colors. Determining the pigment type is paramount and here we investigate the differences in spectrum reflectance for six pigments resulting in red colorations in feathers of different species, with a focus on discriminating among melanins and carotenoids. Pigment chemical identification was obtained from the literature or using High Performance Liquid Chromatography (HPLC) in our laboratory. We have also derived discriminant formulas for identification of the major known types of pigments based on parameters of the reflectance curves obtained with a portable spectrometer. Our results indicate that the reflectance patterns of coloration perceived as red patches widely differ. The distinction between carotenoid- and melanin-based reflectance curves is relatively straightforward: sigmoid versus straight slope. The spectral reflectance curves of feathers containing red psittacofulvins are sigmoid, whereas iron oxide and porphyrin-containing feathers recall pheomelanins in rendering a straight slope. In the case of turacin-based coloration, the spectral shape is unique. For the pigments with enough number of species sampled (i.e., carotenoids, melanins and psittacofulvins) the differences in reflectance shape are important enough to allow separation of carotenoid and melanin derived colorations based on reflectance curves alone.


Assuntos
Aves , Plumas/química , Pigmentos Biológicos/química , Animais , Carotenoides/química , Melaninas/química , Análise Espectral
16.
Actas Dermosifiliogr ; 98(5): 332-44, 2007 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-17555676

RESUMO

INTRODUCTION: Nonmelanoma skin cancer is the most prevalent and incident tumor in the world, being sun exposure the most important risk factor. Childhood and adolescence are the periods where sun exposure is greatest. An intervention to modify sun-related behaviours is essential for skin cancer prophylaxis. MATERIAL AND METHODS: We carried out a quasi-experimental study on a school population of Granada with ages ranging from 11-12 years. The control and study groups completed a questionnaire prior to the intervention with educational program and thereafter. We performed a random conglomerate sampling of 628 teenagers. Statistical analysis was carried out using the Mc Nemar and Wilcoxon tests. RESULTS: After the intervention, the study group showed marked improvement in the results concerning knowledge about sun exposure and skin (OR = 2.89), sun exposure and environment (OR = 2.23), and sun exposure and health (OR = 1.4) as well as in attitudes and healthy behaviour regarding sun exposure (OR = 4.2). This difference was statistically significant compared to the control group. CONCLUSIONS: 1. Before planning a campaign for primary prophylaxis of skin cancer it is necessary to know the information and knowledge of the target population. 2. The risk of acute, intermittent sun exposure and the use of different means of photoprotection should be stressed. 3. In our study group the rate of sun burn has decreased.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Neoplasias Cutâneas/prevenção & controle , Criança , Feminino , Humanos , Masculino , Instituições Acadêmicas , Luz Solar/efeitos adversos , Inquéritos e Questionários
17.
Actas dermo-sifiliogr. (Ed. impr.) ; 98(5): 332-334, jun. 2007. ilus, tab
Artigo em Es | IBECS | ID: ibc-055569

RESUMO

Introducción. El cáncer de piel melanoma y no-melanoma es el tumor más prevalente y más frecuente en el mundo, la exposición solar es el factor de riesgo más importante. La infancia y la adolescencia es el periodo de la vida en el cual la exposición solar es mayor. La intervención para modificar hábitos ante el sol es fundamental para la prevención del cáncer cutáneo. Material y métodos. Realizamos un estudio cuasiexperimental sobre una población escolar de Granada capital de 11 y 12 años con un test previo a casos y controles, intervención con programa educativo a grupo de casos y test posterior a ambos grupos. Muestreo aleatorio por conglomerados. Cuestionario autocumplimentado. Muestra de 628 adolescentes de colegios e institutos de Granada. Estadístico utilizado: Test de Mc Nemar y Wilcoxon. Resultados. Tras la intervención, el grupo de casos mejoraba ampliamente los resultados tanto en conocimientos sobre sol y piel (OR = 2,89), sol y medio ambiente (OR = 2,23) y sol y salud (OR = 1,4) como en actitudes y conductas sanas con respecto al sol, (OR = 4,2), siendo esta diferencia estadísticamente significativa, frente al grupo control. Conclusiones. Antes de planificar una campaña de prevención primaria de cáncer de piel es necesario saber los conocimientos y comportamientos de la población a la que se dirige. En segundo lugar se debe insistir en el riesgo de la exposición solar intermitente aguda y en el uso de los diferentes medios de fotoprotección. Por último hay que señalar que en el grupo de nuestro estudio ha disminuido la frecuencia de quemadura solar


Introduction. Nonmelanoma skin cancer is the most prevalent and incident tumor in the world, being sun exposure the most important risk factor. Childhood and adolescence are the periods where sun exposure is greatest. An intervention to modify sun-related behaviours is essential for skin cancer prophylaxis. Material and methods.We carried out a quasi-experimental study on a school population of Granada with ages ranging from 11-12 years. The control and study groups completed a questionnaire prior to the intervention with educational program and thereafter. We performed a random conglomerate sampling of 628 teenagers. Statistical analysis was carried out using the Mc Nemar and Wilcoxon tests. Results. After the intervention, the study group showed marked improvement in the results concerning knowledge about sun exposure and skin (OR = 2.89), sun exposure and environment (OR = 2.23), and sun exposure and health (OR = 1.4) as well as in attitudes and healthy behaviour regarding sun exposure (OR = 4.2). This difference was statistically significant compared to the control group. Conclusions. 1. Before planning a campaign for primary prophylaxis of skin cancer it is necessary to know the information and knowledge of the target population. 2. The risk of acute, intermittent sun exposure and the use of different means of photoprotection should be stressed. 3. In our study group the rate of sun burn has decreased


Assuntos
Masculino , Feminino , Criança , Humanos , Exposição à Radiação , Avaliação de Resultado de Ações Preventivas , Neoplasias Cutâneas/prevenção & controle , Serviços de Saúde Escolar , Radiação Solar , Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde/métodos
19.
Mol Ecol ; 16(3): 477-86, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17257107

RESUMO

The fragmentation of a population may have important consequences for population genetic diversity and structure due to the effects of genetic drift and reduced gene flow. We studied the genetic consequences of the fragmentation of the Spanish imperial eagle (Aquila adalberti) population into small patches through a temporal analysis. Thirty-four museum individuals representing the population predating the fragmentation were analysed for a 345-bp segment of the mitochondrial control region and a set of 10 nuclear microsatellite loci. Data from a previous study on the current population (N = 79) were re-analysed for this subset of 10 microsatellite markers and results compared to those obtained from the historical sample. Three shared mitochondrial haplotypes were found in both populations, although fluctuations in haplotype frequencies and the occurrence of a fourth haplotype in the historical population resulted in lower current levels of haplotype and nucleotide diversity. However, microsatellite markers revealed undiminished levels of nuclear diversity. No evidence for genetic structure was observed for the historical Spanish imperial eagle population, suggesting that the current pattern of structure is the direct consequence of population fragmentation. Temporal fluctuations in mitochondrial and microsatellite allelic frequencies were found between the historical and the current population as well as for each pairwise comparison between historical and current Centro and historical and current Parque Nacional de Doñana nuclei. Our results indicate an ancestral panmictic situation for the species that management policies should aim to restore. A historical analysis like the one taken here provides the baseline upon which the relative role of recent drift in shaping current genetic patterns in endangered species can be evaluated and this knowledge is used to guide conservation actions.


Assuntos
Águias/genética , Variação Genética , Animais , DNA Mitocondrial/genética , Fluxo Gênico , Deriva Genética , Haplótipos , História do Século XX , Repetições de Microssatélites , Museus , Dinâmica Populacional , Espanha , Fatores de Tempo
20.
Mol Ecol ; 16(3): 629-38, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17257118

RESUMO

The ruddy duck, Oxyura jamaicensis, was introduced to Great Britain in the mid-20th century and has recently spread to other Western European countries. In Spain, ruddy ducks hybridize with the globally endangered white-headed duck, Oxyura leucocephala. We assessed the effects of hybridization on the Spanish white-headed ducks, which constitute 25% of the global population of this species, using a panel of eight nuclear intron markers, 10 microsatellite loci, and mtDNA control region sequences. These data allowed parental individuals, F(1) hybrids, and the progeny of backcrossing to be reliably distinguished. We show that hybrids between the two species are fertile and produce viable offspring in backcrosses with both parental species. To date, however, we found no extensive introgression of ruddy duck genes into the Spanish white-headed duck population, probably due to the early implementation of an effective ruddy duck and hybrid control programme. We also show that genetic diversity in the expanding European ruddy duck population, which was founded by just seven individuals, exceeds that of the native Spanish white-headed duck population, which recently recovered from a severe bottleneck. Unless effective control of ruddy ducks is continued, genetic introgression will compromise the unique behavioural and ecological adaptations of white-headed ducks and consequently their survival as a genetically and evolutionary distinct species.


Assuntos
Patos/genética , Hibridização Genética , Animais , Conservação dos Recursos Naturais , DNA Mitocondrial/genética , Patos/anatomia & histologia , Feminino , Variação Genética , Íntrons , Região de Controle de Locus Gênico , Masculino , Repetições de Microssatélites , Espanha
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