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1.
Microb Ecol ; 83(1): 202-215, 2022 Jan.
Article in English | MEDLINE | ID: mdl-33758979

ABSTRACT

Exposure to environmental stressors, an increasingly recurring event in natural communities due to anthropogenic-induced environmental change, profoundly impacts disease emergence and spread. One mechanism through which this occurs is through stress-induced immunosuppression increasing disease susceptibility, prevalence, intensity and reactivation in hosts. We experimentally evaluated how exposure to stressors affected both the physiology of avian hosts and the prevalence of the zoonotic bacteria Borrelia burgdorferi sensu lato (s.l.), in two model species-the blackbird Turdus merula and the robin Erithacus rubecula captured in the wild, using xenodiagnoses and analysis of skin biopsies and blood. Although exposure to stressors in captivity induced physiological stress in birds (increased the number of circulating heterophils), there was no evidence of increased infectivity to xenodiagnostic ticks. However, Borrelia detection in the blood for both experimental groups of blackbirds was higher by the end of the captivity period. The infectivity and efficiency of transmission were higher for blackbirds than robins. When comparing different methodologies to determine infection status, xenodiagnosis was a more sensitive method than skin biopsies and blood samples, which could be attributed to mild levels of infection in these avian hosts and/or dynamics and timing of Borrelia infection relapses and redistribution in tissues.


Subject(s)
Borrelia burgdorferi Group , Borrelia burgdorferi , Borrelia , Ixodes , Lyme Disease , Songbirds , Animals , Borrelia burgdorferi Group/physiology , Ixodes/microbiology , Lyme Disease/microbiology , Lyme Disease/veterinary , Songbirds/microbiology
2.
J Evol Biol ; 27(12): 2798-806, 2014 12.
Article in English | MEDLINE | ID: mdl-25371062

ABSTRACT

Selection due to social interactions comprises competition over matings (sexual selection stricto sensu) plus other forms of social competition and cooperation. Sexual selection explains sex differences in ornamentation and in various other phenotypes, but does not easily explain cases where those phenotypes are similar in males and females. Understanding such similarities requires knowing how phenotypes influence nonsexual social interactions as well, which can be very important in gregarious animals, but whose role for phenotypic evolution has been overlooked. For example, 'mate choice' experiments often found preferences for ornamentation, but have not assessed whether those are strictly sexual or are general social preferences. Using choice experiments with a gregarious and mutually ornamented finch, the common waxbill (Estrilda astrild), we show that preferences for ornamentation in the opposite-sex also extend to same-sex interactions. Waxbills discriminated between opposite- and same-sex individuals, but most preferences for colour traits were similar when interacting with either sex. Similar preferences in sexual and nonsexual associations may be widespread in nature, either as social adaptations or as by-product of mate preferences. In either case, such preferences may set the stage for the evolution of mutual ornamentation and of various other similarities between the sexes.


Subject(s)
Animal Communication , Finches/physiology , Mating Preference, Animal/physiology , Phenotype , Social Behavior , Animals , Choice Behavior/physiology , Color , Female , Male , Portugal , Principal Component Analysis , Sex Factors
3.
Mol Phylogenet Evol ; 58(2): 271-82, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21044888

ABSTRACT

We present a molecular phylogeny of bullfinches (Pyrrhula Brisson, 1760) based on 2357bp DNA sequence information of mitochondrial genes (cyt-b, 16S rRNA) and nuclear introns (fib-7, GAPDH-11). The genus is clearly a monophyletic group. Within the limits of Pyrrhula, molecular methods support the subdivision of three main groups: (1) "Southeast-Asian bullfinches" (P. nipalensis and P. leucogenis), (2) "Himalayan bullfinches" (P. aurantiaca, P. erythaca, P. erythrocephala), and (3) "Eurasian bullfinches" (P. pyrrhula s.l.). Within the last group there are four different subgroups: (3a) P. (p.) murina, (3b) P. (p.) cineracea, (3c) P. (p.) griseiventris, and (3d) P. pyrrhula s.str. The centre of origin of the genus Pyrrhula was most probably Southeast Asia. Incomplete lineage sorting of both mitochondrial and nuclear genes is observed among two apparently good species (P. erythaca and P. erythrocephala) indicating a very recent speciation event within the Himalayan Mountain chain. According to our estimates, the Pyrrhula ancestors split from the Pinicola ancestors before the Pleistocene. Apart from the subsequent Pre-Pleistocene splits of the three ancestral main groups, most of the diversification of today's representatives probably took place during the past 600,000 years, possibly in interaction with Pleistocene refugia and successive colonization movements after the last glaciation. Thus our work confirms the traditional delimitation of the bullfinches towards the other members of the finch family Fringillidae and corroborates most of the classic intra-generic subdivisions.


Subject(s)
Evolution, Molecular , Finches/genetics , Phylogeny , Animals , Asia , Cell Nucleus/genetics , DNA, Mitochondrial/genetics , Europe , Finches/classification , Genetic Variation , Introns/genetics , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
4.
Clin Cardiol ; 32(9): 488-90, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19743492

ABSTRACT

Infectious thoracic aortitis (IA) remains a rare disease, especially after the appearance of antibiotics. However, if left untreated it is always lethal. It usually affects patients with atherosclerotic aortic disease and/or infective endocarditis. Mycotic aneurysm is the most common form of presentation, although a few reports of nonaneurysmal infectious thoracic aortitis have also been described. Various microorganisms have been associated with infectious thoracic aortitis, most commonly Staphylococcal, Enterococcus, Streptococcus, and Salmonella species. It is extremely important to establish an early diagnosis of IA, because this condition is potentially life-threatening. However, diagnosis is frequently delayed since clinical manifestations are usually nonspecific. Antibiotherapy in combination with complete surgical excision of the infected aorta is the best choice of treatment.


Subject(s)
Aneurysm, Infected/microbiology , Aorta, Thoracic/microbiology , Aortic Aneurysm, Thoracic/microbiology , Aortitis/microbiology , Aneurysm, Infected/diagnosis , Aneurysm, Infected/therapy , Anti-Bacterial Agents/therapeutic use , Aorta, Thoracic/surgery , Aortic Aneurysm, Thoracic/diagnosis , Aortic Aneurysm, Thoracic/therapy , Aortitis/diagnosis , Aortitis/therapy , Aortography/methods , Combined Modality Therapy , Echocardiography, Transesophageal , Humans , Magnetic Resonance Angiography , Tomography, X-Ray Computed , Treatment Outcome , Vascular Surgical Procedures
5.
Mar Pollut Bull ; 54(6): 678-90, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17395214

ABSTRACT

A spatially dynamic model for the productivity of spores and adults of green macroalgae (Enteromorpha sp.) was developed for a mesotidal estuary (Mondego estuary, Portugal). Many of the algal processes and parameters included in the model were experimentally obtained. Model predictions were compared to a real time series (1993-1997) of macroalgal biomass variation and the two sets show a good agreement (ANOVA, P<0.001). Results suggest that algal growth is highly sensitive to small changes in depth and exhibits different patterns of variation in different seasons. On a yearly basis, global calculations for the south channel of the estuary (137 ha) suggest that during bloom years, macroalgal biomass may reach about 21,205 ton DW compared to 240 ton DW in regular years. On a seasonal basis, the difference may be even more significant. The consequences of such variations on the nitrogen and phosphorus loading of the system and the adjacent coastal area are discussed.


Subject(s)
Rivers/chemistry , Ulva/growth & development , Biomass , Geographic Information Systems , Models, Biological , Nitrogen/analysis , Phosphorus/analysis , Portugal , Seasons , Ulva/metabolism , Ulva/physiology , Water Movements
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