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1.
J Environ Radioact ; 274: 107397, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367584

RESUMO

Bird feathers have been widely used as environmental indicators, providing key information on environmental pollution. However, there is little available information on the adsorption of natural radioactivity in bird feathers and consequently, its impact on the field of movement ecology is not yet known. This study investigates the concentration and distribution of 210Pb in wing- and tail-feathers of different bird species with contrasting migratory strategies, and discusses its potential use as a tracer of age and flight times. Adsorption of 210Pb in bird feathers is directly related to the interaction of feathers with air, therefore it is hypothesised that the presence of this radionuclide is proportional to the length of flight times, and is asymmetrically distributed in flight feathers. Consequently, a significant difference is expected between 210Pb concentrations in feathers of long-distance migrants when compared to sedentary species. For this purpose, a total of 45 samples from eight individuals of three bird species with distinct migratory strategies were analysed: a highly aerial and long-distance migratory species (Common swift Apus apus), and two largely sedentary species widely distributed across Europe (Great tit Parus major and Tawny owl Strix aluco). Novel findings show that the content of 210Pb in bird feathers of adult migratory birds is much higher than in sedentary birds or juvenile individuals, demonstrating this naturally occurring radionuclide can provide information about the contact time between feathers and air. Additionally, 210Pb adsorption was not evenly distributed in bird feathers. The findings provide a new method to trace age and flight time of birds using 210Pb in feathers, complementing conventional techniques in bird migration studies.


Assuntos
Chumbo , Monitoramento de Radiação , Animais , Aves , Monitoramento Ambiental/métodos , Plumas , Radioisótopos
2.
Sci Rep ; 13(1): 2545, 2023 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-36781888

RESUMO

A recurrent behavioral trait model to study adaptation to urban environments is the flight initiation distance (FID), measured as the distance at which animals flee from an approaching threat. It has previously been shown that urban birds display shorter FID than their non-urban (rural) counterparts. However, discerning whether this is the result of habituation to human presence and frequentation, or of ecological factors related to the size of the city (considered as "systemic habituation"), has not yet been addressed. In this study, we analyzed House Sparrow (Passer domesticus) FIDs in a network of 26 small towns and villages within the same region in northeastern Spain. Our aim was to relate FID to human population density and settlement size. If the habituation to human presence hypothesis was supported, we should expect FIDs to decrease with the density of the human population across the human settlements, since this type of habituation is related to the rate of human exposure and this is proportional to human density. However, if the systemic habituation hypothesis was supported, FIDs should instead relate to the size of the human settlements, as the abundance of predators, similarly to other ecological variables, is often proportional to the size of towns. Results showed House Sparrows to be bolder in larger human settlements, but not necessarily the ones with a higher density of human population. This supports the idea that the fact that urban birds display shorter FIDs than their rural counterparts is the result of systemic ecological factors rather than the results of a simple habituation to humans.


Assuntos
Adaptação Fisiológica , Aves , Animais , Humanos , Cidades , Espanha
3.
Naturwissenschaften ; 108(3): 18, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33877435

RESUMO

Specimens from zoological collections play a pivotal role in improving scientific knowledge in many natural science disciplines. To guarantee an optimum state of conservation and ensure their usefulness, the preparation process employed is crucial. Skins and skeletons are key elements in vertebrate scientific collections and, ideally, are prepared from recently deceased animals; however, specimens are often stored in a frozen state for a long time (years) prior to preparation. Whether the duration of this frozen state has a deleterious effect on preparation quality has rarely been studied. The main objective of this study was thus to contribute towards research into zoological preparation by testing to see whether prolonged frozen storage hinders the preparation of bird skins and skeletons. We used the common buzzard (Buteo buteo) and the barn owl (Tyto alba) as biological models. Our results showed that long-term frozen storage led to weight loss, bone marrow acidification and solidification, and hampered skin preparation. The necropsy affected weight loss and decreased the skin tear resistance, probably due to tissue dehydration. Thus, prolonged frozen storage appears to have a harmful effect on the preparation quality of vertebrate specimens. Since frozen storage could ultimately have an impact on the conservation and scientific use of museum specimens, practices should be implemented to minimise the amount of time specimens are frozen or to mitigate any detrimental effects. More importance should be attached to research on zoological preparation since it is fundamental for optimising the quality, conservation status, and value of museum collections.


Assuntos
Aves/anatomia & histologia , Congelamento , Museus/estatística & dados numéricos , Esqueleto , Pele , Manejo de Espécimes/normas , Zoologia/métodos , Animais , Fatores de Tempo
4.
Animals (Basel) ; 10(12)2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33266083

RESUMO

Spontaneous prolongation of the luteal phase has been described in horses, but the underlying causes are still unclear. The present study investigated details of gonadotrophin and progestogen secretion in pregnant mares (n = 11) with or without experimentally reduced early postovulatory luteal function. From days 0 to 3 after ovulation, they were treated with the prostaglandin F2α (PGF2α) analogue cloprostenol or left untreated. After conceptus collection on day 34, they were assigned to the opposite treatment. Mares were affiliated to the group primary corpus luteum (n = 6) or diestrous corpus luteum (n = 5) depending on diestrous corpus luteum (CL) detection in the PGF pregnancy. For statistical comparisons, a p-value < 0.05 was significant. There was an effect of treatment (p < 0.01), but not of group on progestogen concentration. The concentration of LH was higher in PGF-treated than in untreated pregnancies (p < 0.05), but did not differ between groups. The FSH concentration did not differ between groups nor treatments. The total luteal tissue area was greater in mares with a diestrous ovulation during the PGF treatment pregnancy. Low progestogen concentration in the early postovulatory phase diminish the negative feedback on the hypothalamic-pituitary axis in early pregnancy and, thus, stimulate a luteal tissue response. Detection of secondary CL at the time of pregnancy examination in mares may reflect that early post-ovulatory progestogen concentrations were low.

5.
Naturwissenschaften ; 105(3-4): 31, 2018 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-29616351

RESUMO

The role of badges as indicators of contest ability has been previously described. In hummingbirds, the exhibition of a badge is expected to save energy expenditure in agonistic interactions and to favor energy intake. Here, we investigate whether variable supercilium size in the white-eared hummingbird has a role in dominance status signaling. Firstly, 45 hummingbird males were captured and their superciliums were photographed to investigate variation in size and any possible allometric relationships. Secondly, 42 male birds were used to analyze whether the supercilium has a role in dominance status signaling in a dyadic contest. We found that supercilium size varied continuously but that despite variability between individuals, there was no relationship between supercilium size and body size. However, our dyad experiment indicated that birds with larger badges were able to make more visits to the feeders than individuals with smaller badges. We suggest a status signaling function of the supercilium.


Assuntos
Comunicação Animal , Aves/anatomia & histologia , Aves/fisiologia , Predomínio Social , Animais , Tamanho Corporal , Masculino
6.
Ecol Evol ; 4(13): 2625-32, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25077014

RESUMO

A standard approach to model how selection shapes phenotypic traits is the analysis of capture-recapture data relating trait variation to survival. Divergent selection, however, has never been analyzed by the capture-recapture approach. Most reported examples of differences between urban and nonurban animals reflect behavioral plasticity rather than divergent selection. The aim of this paper was to use a capture-recapture approach to test the hypothesis that divergent selection can also drive local adaptation in urban habitats. We focused on the size of the black breast stripe (i.e., tie width) of the great tit (Parus major), a sexual ornament used in mate choice. Urban great tits display smaller tie sizes than forest birds. Because tie size is mostly genetically determined, it could potentially respond to selection. We analyzed capture/recapture data of male great tits in Barcelona city (N = 171) and in a nearby (7 km) forest (N = 324) from 1992 to 2008 using MARK. When modelling recapture rate, we found it to be strongly influenced by tie width, so that both for urban and forest habitats, birds with smaller ties were more trap-shy and more cautious than their larger tied counterparts. When modelling survival, we found that survival prospects in forest great tits increased the larger their tie width (i.e., directional positive selection), but the reverse was found for urban birds, with individuals displaying smaller ties showing higher survival (i.e., directional negative selection). As melanin-based tie size seems to be related to personality, and both are heritable, results may be explained by cautious personalities being favored in urban environments. More importantly, our results show that divergent selection can be an important mechanism in local adaptation to urban habitats and that capture-recapture is a powerful tool to test it.

7.
PLoS One ; 9(2): e88224, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24516616

RESUMO

Fire is a major agent involved in landscape transformation and an indirect cause of changes in species composition. Responses to fire may vary greatly depending on life histories and functional traits of species. We have examined the taxonomic and functional responses to fire of eight taxonomic animal groups displaying a gradient of dietary and mobility patterns: Gastropoda, Heteroptera, Formicidae, Coleoptera, Araneae, Orthoptera, Reptilia and Aves. The fieldwork was conducted in a Mediterranean protected area on 3 sites (one unburnt and two burnt with different postfire management practices) with five replicates per site. We collected information from 4606 specimens from 274 animal species. Similarity in species composition and abundance between areas was measured by the Bray-Curtis index and ANOSIM, and comparisons between animal and plant responses by Mantel tests. We analyze whether groups with the highest percentage of omnivorous species, these species being more generalist in their dietary habits, show weak responses to fire (i.e. more similarity between burnt and unburnt areas), and independent responses to changes in vegetation. We also explore how mobility, i.e. dispersal ability, influences responses to fire. Our results demonstrate that differences in species composition and abundance between burnt and unburnt areas differed among groups. We found a tendency towards presenting lower differences between areas for groups with higher percentages of omnivorous species. Moreover, taxa with a higher percentage of omnivorous species had significantly more independent responses of changes in vegetation. High- (e.g. Aves) and low-mobility (e.g. Gastropoda) groups had the strongest responses to fire (higher R scores of the ANOSIM); however, we failed to find a significant general pattern with all the groups according to their mobility. Our results partially support the idea that functional traits underlie the response of organisms to environmental changes caused by fire.


Assuntos
Comportamento Animal/fisiologia , Dieta , Desastres , Incêndios , Movimento/fisiologia , Animais , Especificidade da Espécie
8.
ACS Med Chem Lett ; 3(7): 540-3, 2012 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-24900507

RESUMO

The majority of snakebite envenomations in Central America are caused by the viperid species Bothrops asper, whose venom contains a high proportion of zinc-dependent metalloproteinases that play a relevant role in the pathogenesis of hemorrhage characteristic of these envenomations. Broad metalloproteinase inhibitors, such as the peptidomimetic hydroxamate Batimastat, have been shown to inhibit snake venom metalloproteinases (SVMP). However, the difficulty in having open public access to Batimastat and similar molecules highlights the need to design new inhibitors of SVMPs that could be applied in the treatment of snakebite envenomations. We have chosen the SVMP BaP1 as a model to search for new inhibitors using different strategies, that is, screening of the Prestwick Chemical Library and rational peptide design. Results from these approaches provide clues on the structural requirements for efficient BaP1 inhibition and pave the way for the design of new inhibitors of SVMP.

9.
Biol Lett ; 7(5): 668-9, 2011 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-21450725

RESUMO

Yellow, red or orange carotenoid-based colorations in male birds are often a signal to prospecting females about body condition, health status and ability to find food. However, this general 'ability to find food' has never been defined. Here we show that more brightly ornamented individuals may also be more efficient when foraging in novel situations. The results highlight the fact that evolution may have provided females tools to evaluate cognitive abilities of the males.


Assuntos
Aves/fisiologia , Comportamento Alimentar , Resolução de Problemas , Animais , Cor , Feminino , Masculino
10.
Allergy Asthma Proc ; 29(4): 380-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18702885

RESUMO

Allergic rhinitis (AR) is a common chronic condition in children and may impact a child's quality of life. Increasing treatment compliance may improve quality of life. An oral suspension of fexofenadine hydrochloride (HCl) has been developed to ease administration to children and may, therefore, improve treatment compliance. The purpose of this study was to assess the pharmacokinetic behavior, safety, and tolerability of a single dose of fexofenadine HCl oral suspension administered to children aged 2-5 years with allergic rhinitis. Children (aged 2-5 years) with AR were recruited in a multicenter, open-label, single-dose study. Fexofenadine HCl (30 mg) was administered as a 6-mg/mL suspension (5 mL). Plasma samples were collected up to 24 hours postdose. Adverse events (AEs); electrocardiograms (ECGs); vital signs; and clinical laboratory tests for hematology, blood chemistry, and urinalysis were analyzed to evaluate safety and tolerability. Fifty subjects completed the study. Mean maximum plasma concentration of fexofenadine was 224 ng/mL, and mean area under the plasma concentration curve was 898 ng . hour/mL. Treatment-emergent AEs were mild in intensity and reported in a total of seven subjects. No trends or clinically meaningful changes in mean ECG, vital sign, or clinical laboratory test data occurred during the study. In children aged 2-5 years, the exposure after a 30-mg dose of fexofenadine HCl suspension was similar to the exposures previously seen after a 30- and 60-mg dose of fexofenadine HCl in children aged 6-11 years and in adults, respectively. The suspension was also well tolerated.


Assuntos
Antialérgicos/farmacocinética , Antagonistas não Sedativos dos Receptores H1 da Histamina/farmacocinética , Rinite Alérgica Perene/tratamento farmacológico , Rinite Alérgica Sazonal/tratamento farmacológico , Terfenadina/análogos & derivados , Administração Oral , Antialérgicos/administração & dosagem , Antialérgicos/efeitos adversos , Pré-Escolar , Antagonistas não Sedativos dos Receptores H1 da Histamina/administração & dosagem , Antagonistas não Sedativos dos Receptores H1 da Histamina/efeitos adversos , Humanos , Suspensões , Terfenadina/administração & dosagem , Terfenadina/efeitos adversos , Terfenadina/farmacocinética , Resultado do Tratamento , Estados Unidos
11.
J Asthma ; 44(7): 515-20, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17885853

RESUMO

Intranasal and inhaled corticosteroid administration concurrently in comorbid allergic rhinitis (AR) and asthma may potentially enhance cortisol suppression. This study determined whether intranasal ciclesonide 200 micro g once daily has an additional effect on cortisol suppression when coadministered with inhaled fluticasone propionate-salmeterol (FP-SAL) 500 to 50 micro g twice daily. Adults (N = 150) with perennial AR received FP-SAL and placebo nasal spray during the run-in period. Patients were randomized to ciclesonide or placebo and FP-SAL (43 days). A single 2-mg dose of dexamethasone was administered on the last treatment day. Plasma cortisol decreased during run-in period (p < 0.001), indicating cortisol suppression by FP-SAL. After ciclesonide was added to FP-SAL, plasma cortisol was similar in both groups. Dexamethasone decreased mean plasma cortisol (p < 0.001), demonstrating that further suppression was possible. Ciclesonide coadministered with FP-SAL did not have an additive effect on cortisol suppression compared with FP-SAL.


Assuntos
Albuterol/análogos & derivados , Androstadienos/uso terapêutico , Antialérgicos/uso terapêutico , Broncodilatadores/uso terapêutico , Hidrocortisona/sangue , Pregnenodionas/uso terapêutico , Rinite Alérgica Perene/tratamento farmacológico , Administração por Inalação , Administração Intranasal , Adolescente , Adulto , Albuterol/administração & dosagem , Albuterol/efeitos adversos , Albuterol/uso terapêutico , Androstadienos/administração & dosagem , Androstadienos/efeitos adversos , Antialérgicos/administração & dosagem , Antialérgicos/efeitos adversos , Broncodilatadores/administração & dosagem , Broncodilatadores/efeitos adversos , Método Duplo-Cego , Combinação de Medicamentos , Quimioterapia Combinada , Feminino , Combinação Fluticasona-Salmeterol , Humanos , Masculino , Pessoa de Meia-Idade , Pregnenodionas/administração & dosagem , Pregnenodionas/efeitos adversos
12.
La Paz; El Siglo; 1967. 54 p. ilus.(Manual técnico, n.2).
Monografia em Espanhol | LILACS-Express | LIBOCS, LIBOSP | ID: biblio-1297572

RESUMO

CONTENIDO: 1.La presente monografía intenta llenar un vacío existente en la literatura médica nacional. es cierto que una cantidad inmensa de información sobre nuevas técnicas para el tratamiento del gran quemado llegan al consultorio del médico, pero raramente dispone del tiempo preciso para extractar los datos útiles que pueda poner en práctica sobre todo si no se dedica por entero a la especialidad de la curación de los quemados

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