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1.
Sci Rep ; 12(1): 21220, 2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36482065

RESUMO

American Indian (AI) children experience significant disparities in asthma prevalence, severity, and burden of disease, yet few asthma education interventions are tested in this population. This study aimed to evaluate the efficacy and feasibility of the BREATHE intervention with parents and AI children, during a 3-year follow-up period (n = 108), using a randomized controlled design. Children with asthma identified by electronic medical records (EMR) were screened and matched with 2 controls. The intervention included an initial educational and 24 months of follow-up. The control group continued their usual care. The primary outcome was the frequency of EMR documented, emergency department (ED) visits or hospitalization for respiratory complaints. There was no statistical difference in mean primary outcomes (1.34 (1.98) vs 1.22 (1.95), - 0.88 to 0.63, 95% CI of the difference, p = 0.75), nor percent with any ED visit or hospitalization (29/53, 55% vs 30/55, 54%, p = 0.99) between the intervention or control groups respectively. After 365 days, there was a borderline significant difference in time to primary outcome. Although limited in power, the present study did not demonstrate a persistent effect of this intervention. We recommend that AI pediatric asthma interventions are culturally-designed, use feasible procedures, and repeat education at least every 12 months.


Assuntos
Indígena Americano ou Nativo do Alasca , Pais , Criança , Humanos
2.
PLoS One ; 13(8): e0201563, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30133475

RESUMO

Long-distance migrations influence the physiology, behavior, and fitness of migratory animals throughout their annual cycles, and fundamentally alter their interactions with parasites. Several hypotheses relating migratory behavior to the likelihood of parasitism have entered the literature, making conflicting, testable predictions. To assess how migratory behavior of hosts is associated with parasitism, we compared haemosporidian parasite infections between two closely related populations of a common North American sparrow, the dark-eyed junco, that co-occur in shared habitats during the non-breeding season. One population is sedentary and winters and breeds in the Appalachian Mountains. The other population is migratory and is found in seasonal sympatry with the sedentary population from October through April, but then flies (≥ 900 km) northwards to breed. The populations were sampled in the wild on the shared montane habitat at the beginning of winter and again after confining them in a captive common environment until the spring. We found significantly higher prevalence of haemosporidian parasite infections in the sedentary population. Among infected juncos, we found no difference in parasite densities (parasitemias) between the sedentary and migrant populations and no evidence for winter dormancy of the parasites. Our results suggest that long-distance migration may reduce the prevalence of parasite infections at the population level. Our results are inconsistent with the migratory exposure hypothesis, which posits that long-distance migration increases exposure of hosts to diverse parasites, and with the migratory susceptibility hypothesis, which posits that trade-offs between immune function and migration increase host susceptibility to parasites. However, our results are consistent with the migratory culling hypothesis, which posits that heavily infected animals are less likely to survive long-distance migration, and with the migratory escape hypothesis, which posits that long-distance migration allows host populations to seasonally escape areas of high infection risk.


Assuntos
Migração Animal/fisiologia , Haemosporida/patogenicidade , Infecções Protozoárias em Animais/epidemiologia , Aves Canoras/fisiologia , Animais , Prevalência , Estações do Ano , Comportamento Sedentário , Aves Canoras/parasitologia , Simpatria
3.
PLoS One ; 10(12): e0144587, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26684459

RESUMO

Avian research has begun to reveal associations between candidate genes and migratory behaviors of captive birds, yet few studies utilize genotypic, morphometric, and phenological data from wild individuals. Previous studies have identified an association between ADCYAP1 polymorphism and autumn migratory behavior (restlessness, or zugunruhe), but little is known about the relationship between ADCYAP1 and spring migratory behavior. The timing of spring migration and arrival to the breeding ground are phenological traits which could be particularly favorable for establishing territories and acquiring mates, thus important to fitness and reproductive success. Here, we investigated how individual genotypic ADCYAP1 variation and phenotypic variation (wing length and shape) of blackcaps (Sylvia atricapilla) affect spring arrival date across nine natural populations in Europe. We hypothesized that longer alleles should be associated with earlier spring arrival dates and expected the effect on arrival date to be stronger for males as they arrive earlier. However, we found that longer wings were associated with earlier spring arrival to the breeding grounds for females, but not for males. Another female-specific effect indicated an interaction between ADCYAP1 allele size and wing pointedness on the response of spring arrival: greater allele size had a positive effect on spring arrival date for females with rounder wings, while a negative effect was apparent for females with more pointed wings. Also, female heterozygotes with pointed wing tips arrived significantly earlier than both homozygotes with pointed wings and heterozygotes with round wings. Stable isotope ratios (δ2H) of a subset of blackcaps captured in Freiburg in 2011 allowed us also to assign individuals to their main overwintering areas in northwest (NW) and southwest (SW) Europe. NW males arrived significantly earlier to the Freiburg breeding site than both SW males and females in 2011. NW females had more pointed wing tips compared to SW females, but no difference in ADCYAP1 allele size was found between the different migration routes.


Assuntos
Migração Animal/fisiologia , Passeriformes/fisiologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/genética , Asas de Animais/anatomia & histologia , Animais , Feminino , Masculino , Passeriformes/anatomia & histologia , Passeriformes/genética , Fenótipo , Polimorfismo Genético , Estações do Ano , Fatores Sexuais
4.
PLoS One ; 10(12): e0144264, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26656955

RESUMO

A novel migratory polymorphism evolved within the last 60 years in blackcaps (Sylvia atricapilla) breeding sympatrically in southwestern Germany. While most individuals winter in the traditional areas in the Mediterranean, a growing number of blackcaps started migrating to Britain instead. The rapid microevolution of this new strategy has been attributed to assortative mating and better physical condition of birds wintering in Britain. However, the isolating barriers as well as the physical condition of birds are not well known. In our study, we examined whether spatial isolation occurred among individuals with distinct migratory behaviour and birds with different arrival dates also differed in physical and genetic condition. We caught blackcaps in six consecutive years upon arrival on the breeding grounds and assigned them via stable isotope analysis to their wintering areas. Analysis of the vegetation structure within blackcap territories revealed different microhabitat preferences of birds migrating to distinct wintering areas. Blackcaps arriving early on the breeding grounds had higher survival rates, better body condition and higher multilocus heterozygosities than later arriving birds. We did however not find an effect of parasite infection status on arrival time. Our results suggest that early arriving birds have disproportionate effects on population dynamics. Allochrony and habitat isolation may thus act together to facilitate ongoing divergence in hybrid zones, and migratory divides in particular.


Assuntos
Migração Animal/fisiologia , Passeriformes/genética , Dinâmica Populacional , Isolamento Reprodutivo , Navegação Espacial/fisiologia , Animais , Evolução Biológica , Cruzamento , Alemanha , Marcação por Isótopo , Região do Mediterrâneo , Passeriformes/fisiologia , Condicionamento Físico Animal , Estações do Ano , Reino Unido
5.
PLoS One ; 8(11): e81365, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24278428

RESUMO

Migratory divides are thought to facilitate behavioral, ecological, and genetic divergence among populations with different migratory routes. However, it is currently contentious how much genetic divergence is needed to maintain distinct migratory behavior across migratory divides. Here we investigate patterns of neutral genetic differentiation among Blackcap (Sylvia atricapilla) populations with different migratory strategies across Europe. We compare the level of genetic divergence of populations migrating to southwestern (SW) or southeastern (SE) wintering areas with birds wintering in the British Isles following a recently established northwesterly (NW) migration route. The migratory divide between SW and SE wintering areas can be interpreted as a result of a re-colonization process after the last glaciation. Thus we predicted greater levels of genetic differentiation among the SW/SE populations. However, a lack of genetic differentiation was found between SW and SE populations, suggesting that interbreeding likely occurs among Blackcaps with different migratory orientations across a large area; therefore the SW/SE migratory divide can be seen as diffuse, broad band and is, at best, a weak isolating barrier. Conversely, weak, albeit significant genetic differentiation was evident between NW and SW migrants breeding sympatrically in southern Germany, suggesting a stronger isolating mechanism may be acting in this population. Populations located within/near the SW/SE contact zone were the least genetically divergent from NW migrants, confirming NW migrants likely originated from within the contact zone. Significant isolation-by-distance was found among eastern Blackcap populations (i.e. SE migrants), but not among western populations (i.e. NW and SW migrants), revealing different patterns of genetic divergence among Blackcap populations in Europe. We discuss possible explanations for the genetic structure of European Blackcaps and how gene flow influences the persistence of divergent migratory behaviors.


Assuntos
Migração Animal , Passeriformes/genética , Animais , Evolução Biológica , Europa (Continente) , Feminino , Variação Genética , Genética Populacional , Geografia , Masculino
6.
Mol Ecol Resour ; 13(2): 341-3, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23356940

RESUMO

This article documents the addition of 153 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Brassica oleracea, Brycon amazonicus, Dimorphandra wilsonii, Eupallasella percnurus, Helleborus foetidus, Ipomoea purpurea, Phrynops geoffroanus, Prochilodus argenteus, Pyura sp., Sylvia atricapilla, Teratosphaeria suttonii, Trialeurodes vaporariorum and Trypanosoma brucei. These loci were cross-tested on the following species: Dimorphandra coccicinea, Dimorphandra cuprea, Dimorphandra gardneriana, Dimorphandra jorgei, Dimorphandra macrostachya, Dimorphandra mollis, Dimorphandra parviflora and Dimorphandra pennigera.


Assuntos
Ascomicetos/genética , Bases de Dados Genéticas , Dípteros/genética , Plantas/genética , Trypanosoma brucei brucei/genética , Animais , Ecologia , Repetições de Microssatélites , Dados de Sequência Molecular
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