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1.
R Soc Open Sci ; 5(10): 181227, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30473858

RESUMO

Evaluating how populations are connected by migration is important for understanding species resilience because gene flow can facilitate recovery from demographic declines. We therefore investigated the extent to which migration may have contributed to the global recovery of the Antarctic fur seal (Arctocephalus gazella), a circumpolar distributed marine mammal that was brought to the brink of extinction by the sealing industry in the eighteenth and nineteenth centuries. It is widely believed that animals emigrating from South Georgia, where a relict population escaped sealing, contributed to the re-establishment of formerly occupied breeding colonies across the geographical range of the species. To investigate this, we interrogated a genetic polymorphism (S291F) in the melanocortin 1 receptor gene, which is responsible for a cream-coloured phenotype that is relatively abundant at South Georgia and which appears to have recently spread to localities as far afield as Marion Island in the sub-Antarctic Indian Ocean. By sequencing a short region of this gene in 1492 pups from eight breeding colonies, we showed that S291F frequency rapidly declines with increasing geographical distance from South Georgia, consistent with locally restricted gene flow from South Georgia mainly to the South Shetland Islands and Bouvetøya. The S291F allele was not detected farther afield, suggesting that although emigrants from South Georgia may have been locally important, they are unlikely to have played a major role in the recovery of geographically more distant populations.

2.
Rev Pneumol Clin ; 74(5): 351-358, 2018 Oct.
Artigo em Francês | MEDLINE | ID: mdl-30316650

RESUMO

INTRODUCTION: Malignant pleural mesothelioma (MPM) is a rare and highly aggressive disease, whose incidence is increasing. Asbestos is the primary causal agent. STATE OF KNOWLEDGE: Knowledge about MPM has evolved. Thoracoscopy is essential for diagnosis of MPM. It allows performing pleural biopsies, to study the extent of the disease and to relieve dyspnea. The pathological diagnosis is also better codified with immunohistochemistry and with analysis by expert of Mesopath group. Curative surgical treatments are pleurectomy decortication and extended pneumonectomy in combination with chemotherapy and/or radiotherapy. Those heavy treatments improve survival in highly selected patients. For the other patients, supportive measures will be considered to reduce pain and dyspnea. PROSPECT: Radical surgical treatment is only offered in therapeutic trials or multimodal treatment. Its place is not formally established. New therapies associated to surgical treatment are being studied. CONCLUSIONS: Surgical management of MPM has to be operated in specialized teams where the survival benefit and quality of life is discussed case by case.


Assuntos
Neoplasias Pulmonares/cirurgia , Mesotelioma/cirurgia , Neoplasias Pleurais/cirurgia , Procedimentos Cirúrgicos Torácicos/métodos , Quimioterapia Adjuvante , Terapia Combinada , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Mesotelioma/diagnóstico , Mesotelioma/tratamento farmacológico , Mesotelioma/radioterapia , Mesotelioma Maligno , Neoplasias Pleurais/diagnóstico , Neoplasias Pleurais/tratamento farmacológico , Neoplasias Pleurais/radioterapia , Pneumonectomia , Radioterapia Adjuvante , Toracoscopia , Resultado do Tratamento
4.
Proc Natl Acad Sci U S A ; 115(12): 3072-3077, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29483242

RESUMO

The extent of increasing anthropogenic impacts on large marine vertebrates partly depends on the animals' movement patterns. Effective conservation requires identification of the key drivers of movement including intrinsic properties and extrinsic constraints associated with the dynamic nature of the environments the animals inhabit. However, the relative importance of intrinsic versus extrinsic factors remains elusive. We analyze a global dataset of ∼2.8 million locations from >2,600 tracked individuals across 50 marine vertebrates evolutionarily separated by millions of years and using different locomotion modes (fly, swim, walk/paddle). Strikingly, movement patterns show a remarkable convergence, being strongly conserved across species and independent of body length and mass, despite these traits ranging over 10 orders of magnitude among the species studied. This represents a fundamental difference between marine and terrestrial vertebrates not previously identified, likely linked to the reduced costs of locomotion in water. Movement patterns were primarily explained by the interaction between species-specific traits and the habitat(s) they move through, resulting in complex movement patterns when moving close to coasts compared with more predictable patterns when moving in open oceans. This distinct difference may be associated with greater complexity within coastal microhabitats, highlighting a critical role of preferred habitat in shaping marine vertebrate global movements. Efforts to develop understanding of the characteristics of vertebrate movement should consider the habitat(s) through which they move to identify how movement patterns will alter with forecasted severe ocean changes, such as reduced Arctic sea ice cover, sea level rise, and declining oxygen content.


Assuntos
Migração Animal , Bases de Dados Factuais , Oceanos e Mares , Vertebrados , Animais , Ecossistema
5.
Sci Rep ; 6: 33211, 2016 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-27620663

RESUMO

Investigating the ontogeny of niche differentiation enables to determine at which life-stages sexual segregation arises, providing insights into the main factors driving resource partitioning. We investigated the ontogeny of foraging ecology in Antarctic fur seals (Arctocephalus gazella), a highly dimorphic species with contrasting breeding strategies between sexes. Sequential δ(13)C and δ(15)N values of whiskers provided a longitudinal proxy of the foraging niche throughout the whole life of seals, from weaning, when size dimorphism is minimal to the age of 5. Females exhibited an early-life ontogenetic shift, from a total segregation during their first year at-sea, to a similar isotopic niche as breeding females as early as age 2. In contrast, males showed a progressive change in isotopic niche throughout their development such that 5-year-old males did not share the same niche as territorial bulls. Interestingly, males and females segregated straight after weaning with males appearing to feed in more southerly habitats than females. This spatial segregation was of similar amplitude as observed in breeding adults and was maintained throughout development. Such early-life niche differentiation is an unusual pattern and indicates size dimorphism and breeding constraints do not directly drive sexual segregation contrary to what has been assumed in otariid seals.


Assuntos
Ecossistema , Comportamento Alimentar/fisiologia , Otárias/fisiologia , Comportamento Sexual Animal/fisiologia , Fatores Etários , Animais , Regiões Antárticas , Isótopos de Carbono/metabolismo , Feminino , Masculino , Isótopos de Nitrogênio/metabolismo , Estações do Ano , Fatores Sexuais , Fatores de Tempo , Vibrissas/metabolismo
6.
R Soc Open Sci ; 3(7): 160143, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27493771

RESUMO

Individual specialization is widespread among wild populations. While its fitness consequences are central in predicting the ecological and evolutionary trajectories of populations, they remain poorly understood. Long-term individual foraging specializations occur in male Antarctic (Arctocephalus gazella) and Australian (A. pusillus doriferus) fur seals. Strong selective pressure is expected in these highly dimorphic and polygynous species, raising the question of the fitness payoffs associated with different foraging strategies. We investigated the relationship between individual isotopic niche (a proxy of foraging specialization), body size and condition, and an index of reproductive success (harem size) in territorial males. Individuals varied greatly in their skin and fur isotopic values reflecting a range of foraging strategies within the two populations. However, in both species, isotopic niche was not correlated to body size, condition or mating success (R (2)/ρ < 0.06). Furthermore, no foraging niche was predominant in either species, which would have indicated a substantial long-term fitness benefit of a particular strategy via a higher survival rate. These results suggest that the fitness consequences of a foraging strategy depend not only on the quality of prey and feeding habitat but also on an individual's hunting efficiency and skills.

7.
Plant Dis ; 100(12): 2465-2474, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30686173

RESUMO

Brown rot is an economically important fungal disease affecting stone and pome fruit orchards, as well as harvested fruit during storage and on the market. Monilinia fructicola, M. laxa, and M. fructigena are the main causal agents of this disease and each have a different regulatory status depending on regional regulations. In this study, a new multiplex tool based on real-time polymerase chain reaction was developed to detect the three pathogenic fungi in a single reaction on fruit, twigs, and flowers of Prunus and Malus spp. Species-specific primer-hydrolysis probe combinations were designed to amplify a region located in a previously described MO368 sequenced characterized amplified region marker, and used in a quadruplex format coupled with the 18S Uni universal primer-probe test in order to check the quality of the DNA template. The assay was designed and optimized with the objective to provide high performance values. Experimental data supported its sensitivity, specificity, reproducibility, and robustness. In addition, a set of quality controls was implemented to minimize the risk of false-positive and false-negative results, thus making this new test fit for use in serial analyses and reliable in the framework of official controls.

8.
Eur Rev Med Pharmacol Sci ; 18(15): 2094-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25070811

RESUMO

A 56 year-old woman (treated for ovarian cystadenocarcinoma 9-yrs before) presented a slowly increasing dyspnea. CT-scan revealed a mediastinal cyst with typical radiological pattern compatible with benign pleuro-pericardial cyst. The cyst was removed via right thoracoscopy. Surprisingly, the pathology were indicative of cystic mediastinal recurrence from ovarian adenocarcinoma.


Assuntos
Cistadenocarcinoma/patologia , Cisto Mediastínico/patologia , Recidiva Local de Neoplasia/patologia , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/patologia , Carcinoma Epitelial do Ovário , Dispneia/patologia , Dispneia/cirurgia , Feminino , Humanos , Cisto Mediastínico/cirurgia , Pessoa de Meia-Idade
10.
Arch Pediatr ; 19(11): 1200-4, 2012 Nov.
Artigo em Francês | MEDLINE | ID: mdl-23083686

RESUMO

Hepatic alveolar echinococcosis is a rare parasitic zoonosis, potentially lethal in childhood. It is due to Echinococcosis multilocularis whose larva insidiously develops in the liver. We report the case of a 13-year-old girl, living in the Vosges Mountains, followed for recurrent abdominal pain, with recent worsening. Diagnosis of alveolar echinococcosis was immediately suspected based on the liver ultrasound scan and then confirmed by imaging (CT scan, NMR) and serology. A curative surgical treatment (segmentectomy) was performed 3 months after diagnosis, under oral albendazole treatment, maintained for at least 2 years. Hepatic alveolar echinococcosis usually has a negative prognosis, except if diagnosed early, which allows rapid surgical treatment, as in our patient.


Assuntos
Dor Abdominal/etiologia , Dor Abdominal/cirurgia , Equinococose Hepática/diagnóstico , Equinococose Hepática/cirurgia , Adolescente , Diagnóstico Precoce , Equinococose Hepática/transmissão , Feminino , Hepatectomia , Humanos , Espectroscopia de Ressonância Magnética , Recidiva , Tomografia Computadorizada por Raios X , Ultrassonografia
11.
J Evol Biol ; 24(3): 607-16, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21159006

RESUMO

The traditional distinction between ecological and evolutionary times is eroding, calling for tighter links between ecology and evolution. An example of such a brigde between the two disciplines is the so-called 'animal model', a methodology initially developed by animal breeders, which has become very popular among ecologists studying contemporary microevolution. Using a Bayesian multi-trait 'animal model', we investigated the quantitative genetics of body size, a fitness-related trait, in Subantarctic fur seals (Arctocephalus tropicalis) breeding on Amsterdam Island, Southern Ocean. Our approach jointly modelled the growth and selection processes at work in this population. Body length is heritable for both sexes, and females are under selection for increased body length in this population. We strongly suspect the peculiar ecological context of impoverished, suitable prey availability exacerbated by density-dependence phenomena to be an important selective agent on females breeding on Amsterdam Island.


Assuntos
Otárias/genética , Seleção Genética , Adaptação Fisiológica/genética , Animais , Regiões Antárticas , Evolução Biológica , Tamanho Corporal , Feminino , Aptidão Genética , Geografia
13.
Ann Pharm Fr ; 68(6): 359-69, 2010 Nov.
Artigo em Francês | MEDLINE | ID: mdl-21073994

RESUMO

After having been used for decades, heparins (unfractionated heparin [UFH] or low molecular weight heparins [LMWH]) and vitamin K antagonists (VKA), which are only parenterally active or which are responsible for frequent iatrogenicity respectively, have to face the competition of new anticoagulant drugs targeting either factor Xa or factor IIa (thrombin). Rivaroxaban (Xarelto(®)) and Dabigatran Etexilate (Pradaxa(®)) are the two leading components. They are more convenient to use and do not require routine coagulation monitoring. They are already marketed for venous thromboembolism prevention in major orthopaedic surgery. Although manufacturers claim that no biological monitoring is required, these two compounds may interfere in routine coagulation tests such as PT or aPTT, and in esoteric assays such as anti-Xa activity (the results of which are usually expressed in international anti-Xa units either UFH or LMWH unit) for Rivaroxaban or anti-IIa activity for Dabigatran Etexilate. Noteworthy is the fact that, in the case of these new anticoagulant drugs, results should be expressed in active product units (nanogram per millilitre of Rivaroxaban or Dabigatran). The new anticoagulants are associated with a bleeding risk comparable to that of VKA and heparins.


Assuntos
Anticoagulantes/uso terapêutico , Benzimidazóis/uso terapêutico , Morfolinas/uso terapêutico , Piridinas/uso terapêutico , Tiofenos/uso terapêutico , Anticoagulantes/classificação , Anticoagulantes/farmacologia , Benzimidazóis/farmacologia , Testes de Coagulação Sanguínea , Dabigatrana , Inibidores do Fator Xa , Humanos , Morfolinas/farmacologia , Piridinas/farmacologia , Rivaroxabana , Tiofenos/farmacologia , Trombina/antagonistas & inibidores
14.
Biol Lett ; 5(6): 830-2, 2009 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-19793740

RESUMO

The movement and dietary history of individuals can be studied using stable isotope records in archival keratinous tissues. Here, we present a chronology of temporally fine-scale data on the trophic niche of otariid seals by measuring the isotopic signature of serially sampled whiskers. Whiskers of male Antarctic fur seals breeding at the Crozet Islands showed synchronous and regular oscillations in both their delta(13)C and delta(15)N values that are likely to represent their annual migrations over the long term (mean 4.8 years). At the population level, male Antarctic fur seals showed substantial variation in both delta(13)C and delta(15)N values, occupying nearly all the 'isotopic space' created by the diversity of potential oceanic habitats (from high Antarctica to the subtropics) and prey (from Antarctic krill to subantarctic and subtropical mesopelagic fishes). At the individual level, whisker isotopic signatures depict a large diversity of foraging strategies. Some seals remained in either subantarctic or Antarctic waters, while the migratory cycle of most animals encompassed a wide latitudinal gradient where they fed on different prey. The isotopic signature of whiskers, therefore, revealed new multi-year foraging strategies of male Antarctic fur seals and is a powerful tool for investigating the ecological niche during cryptic stages of mammals' life.


Assuntos
Migração Animal , Comportamento Alimentar , Otárias , Vibrissas/química , Animais , Isótopos de Carbono/análise , Masculino , Isótopos de Nitrogênio/análise
15.
Proc Natl Acad Sci U S A ; 105(33): 11634-9, 2008 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-18695241

RESUMO

Polar regions are particularly sensitive to climate change, with the potential for significant feedbacks between ocean circulation, sea ice, and the ocean carbon cycle. However, the difficulty in obtaining in situ data means that our ability to detect and interpret change is very limited, especially in the Southern Ocean, where the ocean beneath the sea ice remains almost entirely unobserved and the rate of sea-ice formation is poorly known. Here, we show that southern elephant seals (Mirounga leonina) equipped with oceanographic sensors can measure ocean structure and water mass changes in regions and seasons rarely observed with traditional oceanographic platforms. In particular, seals provided a 30-fold increase in hydrographic profiles from the sea-ice zone, allowing the major fronts to be mapped south of 60 degrees S and sea-ice formation rates to be inferred from changes in upper ocean salinity. Sea-ice production rates peaked in early winter (April-May) during the rapid northward expansion of the pack ice and declined by a factor of 2 to 3 between May and August, in agreement with a three-dimensional coupled ocean-sea-ice model. By measuring the high-latitude ocean during winter, elephant seals fill a "blind spot" in our sampling coverage, enabling the establishment of a truly global ocean-observing system.


Assuntos
Gelo , Focas Verdadeiras , Água do Mar , Animais , Temperatura
17.
Proc Natl Acad Sci U S A ; 104(34): 13705-10, 2007 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-17693555

RESUMO

Responses by marine top predators to environmental variability have previously been almost impossible to observe directly. By using animal-mounted instruments simultaneously recording movements, diving behavior, and in situ oceanographic properties, we studied the behavioral and physiological responses of southern elephant seals to spatial environmental variability throughout their circumpolar range. Improved body condition of seals in the Atlantic sector was associated with Circumpolar Deep Water upwelling regions within the Antarctic Circumpolar Current, whereas High-Salinity Shelf Waters or temperature/salinity gradients under winter pack ice were important in the Indian and Pacific sectors. Energetic consequences of these variations could help explain recently observed population trends, showing the usefulness of this approach in examining the sensitivity of top predators to global and regional-scale climate variability.


Assuntos
Comportamento Predatório/fisiologia , Migração Animal , Animais , Caniformia/fisiologia , Ecologia , Oceanografia , Dinâmica Populacional , Estações do Ano
18.
Artigo em Inglês | MEDLINE | ID: mdl-15123189

RESUMO

Lactating fur seals (Arctocephalus tropicalis) alternate foraging trips at sea and pup attendance periods ashore. During the onshore nursing periods, lactating females do not have access to food and meet both their own metabolic requirements and milk production from their body reserve. Blood and milk samples were collected from females captured soon after their arrival ashore from a foraging trip and before their departure. Milk lipid but not milk protein content was positively related to the body condition index (BCI) of the female. During the 4-day attendance period ashore, females lost body mass, and plasma cortisol levels increased, whereas plasma urea concentration decreased and beta-hydroxybutyrate (beta-OHB) remained unchanged. The increase in cortisol level took place while blood urea concentration decreased and beta-OHB remained at a low level suggesting that it was independent from the transition from phase II to phase III that is indicative of the depletion of lipid body store as described in penguins. Thus, our results suggest that the increase in cortisol level in relation to decreasing BCI may either contribute to the mobilization of protein stores to ensure milk production when easily mobilized stores are used and/or could act as a re-feeding signal which is triggered well before females have depleted their body store.


Assuntos
Otárias/fisiologia , Hidrocortisona/sangue , Lactação/fisiologia , Ácido 3-Hidroxibutírico/sangue , Animais , Animais Recém-Nascidos , Regiões Antárticas , Peso Corporal , Jejum , Feminino , Hidrocortisona/metabolismo , Lipídeos/análise , Lipídeos/química , Leite/química , Ureia/sangue
19.
J Exp Biol ; 206(Pt 24): 4497-506, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14610034

RESUMO

The period of maternal dependence is a time during which mammalian infants must optimise both their growth and the development of behavioural skills in order to successfully meet the demands of independent living. The rate and duration of maternal provisioning, post-weaning food availability and climatic conditions are all factors likely to influence the growth strategies of infants. While numerous studies have documented differences in growth strategies at high taxonomic levels, few have investigated those of closely related species inhabiting similar environments. The present study examined the body composition, metabolism and indices of physiological development in pups of Antarctic fur seals (Arctocephalus gazella) and subantarctic fur seals (Arctocephalus tropicalis), congeneric species with different weaning ages (4 months and 10 months, respectively), during their overlap in lactation at a sympatric breeding site in the Iles Crozet. Body lipid reserves in pre-moult pups were significantly greater (t28=2.73, P<0.01) in subantarctic (26%) than Antarctic fur seals (22%). Antarctic fur seal pups, however, had significantly higher (t26=3.82, P<0.001) in-air resting metabolic rates (RMR; 17.1 +/- 0.6 ml O2 kg(-1) min(-1)) than subantarctic fur seal pups (14.1 +/- 0.5 ml O2 kg(-1) min(-1)). While in-water standard metabolic rate (SMR; 22.9 +/- 2.5 ml O2 kg(-1) min(-1)) was greater than in-air RMR for Antarctic fur seal pups (t9=2.59, P<0.03), there were no significant differences between in-air RMR and in-water SMR for subantarctic fur seal pups (t12=0.82, P>0.4), although this is unlikely to reflect a greater ability for pre-moult pups of the latter species to thermoregulate in water. Pup daily energy expenditure was also significantly greater (t27=2.36, P<0.03) in Antarctic fur seals (638 +/- 33 kJ kg(-1) day(-1)) than in subantarctic fur seals (533 +/- 33 kJ kg(-1) day(-1)), which corroborates observations that pups of the former species spend considerably more time actively learning to swim and dive. Consistent with this observation is the finding that blood oxygen storage capacity was significantly greater (t9=2.81, P<0.03) in Antarctic (11.5%) than subantarctic fur seal (8.9%) pups. These results suggest that, compared with subantarctic fur seals, Antarctic fur seal pups adopt a strategy of faster lean growth and physiological development, coupled with greater amounts of metabolically expensive behavioural activity, in order to acquire the necessary foraging skills in time for their younger weaning age.


Assuntos
Metabolismo Energético/fisiologia , Otárias/crescimento & desenvolvimento , Leite/fisiologia , Atividade Motora/fisiologia , Animais , Animais Lactentes , Regiões Antárticas , Metabolismo Basal , Composição Corporal , Geografia , Oxigênio/sangue , Especificidade da Espécie
20.
Physiol Biochem Zool ; 74(4): 548-59, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11436139

RESUMO

Milk composition was investigated throughout the 10-mo pup-rearing period in subantarctic fur seals (Arctocephalus tropicalis) breeding on Amsterdam Island. The mean milk composition was 42.8% +/- 5.7% lipid, 12.1% +/- 1.5% protein, and 42.6% +/- 7.3% water. Subantarctic fur seals breeding on Amsterdam Island produced one of the richest milks ever reported in otariids (20.4 +/- 2.9 kJ/g), with lipid content contributing 85% of total gross energy. The high lipid levels measured in the milk of subantarctic fur seals breeding on Amsterdam Island is consistent (i) with the relatively long time lactating females spend at sea, due to the relatively poor local trophic conditions near the colony that necessitate that they travel long distances to reach the foraging grounds, and (ii) with the consequently short time mothers spend with their pups ashore. Milk composition changed according to the time mothers were fasting ashore: milk produced during the first 2 d spent ashore, when more than 80% of milk transfer occurred, had higher levels of lipids, proteins, and gross energy than milk produced later during the visit ashore, suggesting that the pups were fed with two types of milk during a suckling period. Throughout the year, mothers in good condition produced milk of higher lipid content than others, suggesting that individual foraging skills contribute to enhance milk quality. Milk lipid and gross energy content varied with pup age, according to quadratic relationships, increasing during the earlier stages of lactation before reaching asymptotic values when pups were 180 d old. The stage of lactation appears to be a better predictor of milk lipid content than the duration of the preceding foraging trip, suggesting that either changes in the nutritional requirements of the pup and/or seasonal changes in trophic conditions act on milk composition. These changes in milk quality may also be related to changes in maternal care; lactating subantarctic fur seals apparently reallocate their body reserves toward gestation rather than lactation at the end of the pup-rearing period.


Assuntos
Otárias/fisiologia , Lactação/fisiologia , Leite/metabolismo , Animais , Animais Lactentes , Peso Corporal , Comportamento Alimentar/fisiologia , Feminino , Otárias/metabolismo , Otárias/psicologia , Ilhas do Oceano Índico , Lactação/metabolismo , Lactação/psicologia , Metabolismo dos Lipídeos , Leite/química , Proteínas do Leite/metabolismo , Estações do Ano
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