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1.
Ecohealth ; 15(4): 777-791, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30117001

RESUMEN

From 2006 through 2014, we conducted seroepidemiological surveys on non-human primates and sloths to investigate the possible circulation of arboviruses in Bahia Atlantic Forest, Brazil. We collected a total of 196 samples from 103 Leontopithecus chrysomelas, 7 Sapajus xanthosternos, 22 Bradypus torquatus and 7 Bradypus variegatus. Serum samples were tested using neutralization test and hemagglutination inhibition test to detect total antibodies against 26 different arboviruses. The overall prevalence of arboviruses was 36.6% (51/139), with the genus Flavivirus having the highest prevalence (33.1%; 46/139), followed by Phlebovirus (5.0%; 7/139), Orthobunyavirus (4.3%; 6/139) and Alphavirus (0.7%; 1/139). Monotypic reactions suggest that the wild animals were exposed naturally to at least twelve arboviruses. Added results from the neutralization test, animals were exposed to thirteen arboviruses. Most of these viruses are maintained in transmission cycles independent of human hosts, although antibodies against dengue virus serotypes 1, 2 and 3 were found in this study. To our knowledge, this is the first study reporting exposure to arboviruses in L. chrysomelas, S. xanthosternos and B. torquatus. Our results also highlight that the Southern Bahia Atlantic Forest has a variety of vertebrate hosts and potential vectors, which may support the emergence or re-emergence of arboviruses, including those pathogenic to humans.


Asunto(s)
Infecciones por Arbovirus/epidemiología , Infecciones por Arbovirus/veterinaria , Arbovirus/aislamiento & purificación , Primates/virología , Perezosos/virología , Animales , Brasil/epidemiología , Femenino , Masculino , Estudios Seroepidemiológicos , Pruebas Serológicas
2.
Conserv Biol ; 27(6): 1366-77, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24033638

RESUMEN

Haemosporidian parasites in the genus Plasmodium were recently detected through molecular screening in the Galapagos Penguin (Spheniscus mendiculus). We summarized results of an archipelago-wide screen of 3726 endemic birds representing 22 species for Plasmodium spp. through a combination of molecular and microscopy techniques. Three additional Plasmodium lineages were present in Galapagos. Lineage A-infected penguins, Yellow Warblers (Setophaga petechia aureola), and one Medium Ground Finch (Geospiza fortis) and was detected at multiple sites in multiple years [corrected]. The other 3 lineages were each detected at one site and at one time; apparently, they were transient infections of parasites not established on the archipelago. No gametocytes were found in blood smears of infected individuals; thus, endemic Galapagos birds may be dead-end hosts for these Plasmodium lineages. Determining when and how parasites and pathogens arrive in Galapagos is key to developing conservation strategies to prevent and mitigate the effects of introduced diseases. To assess the potential for Plasmodium parasites to arrive via migratory birds, we analyzed blood samples from 438 North American breeding Bobolinks (Dolichonyx oryzivorus), the only songbird that regularly migrates through Galapagos. Two of the ephemeral Plasmodium lineages (B and C) found in Galapagos birds matched parasite sequences from Bobolinks. Although this is not confirmation that Bobolinks are responsible for introducing these lineages, evidence points to higher potential arrival rates of avian pathogens than previously thought. Linajes Múltiples de Parásitos de Malaria Aviar (Plasmodium) en las Islas Galápagos y Evidencia de su Arribo por Medio de Aves Migratorias.


Asunto(s)
Migración Animal , Aves/parasitología , Conservación de los Recursos Naturales , Plasmodium/clasificación , Animales , ADN Protozoario/química , Ecuador , Especies Introducidas , Filogenia , Plasmodium/genética , Plasmodium/aislamiento & purificación
3.
J Evol Biol ; 25(3): 509-21, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22239606

RESUMEN

The faunas associated with oceanic islands provide exceptional examples with which to examine the dispersal abilities of different taxa and test the relative contribution of selective and neutral processes in evolution. We examine the patterns of recent differentiation and the relative roles of gene flow and selection in genetic and morphological variation in the yellow warbler (Dendroica petechia aureola) from the Galápagos and Cocos Islands. Our analyses suggest aureola diverged from Central American lineages colonizing the Galápagos and Cocos Islands recently, likely less than 300 000 years ago. Within the Galápagos, patterns of genetic variation in microsatellite and mitochondrial markers suggest early stages of diversification. No intra-island patterns of morphological variation were found, even across steep ecological gradients, suggesting that either (i) high levels of gene flow may be homogenizing the effects of selection, (ii) populations may not have had enough time to accumulate the differences in morphological traits, or (iii) yellow warblers show lower levels of 'evolvability' than some other Galápagos species. By examining genetic data and morphological variation, our results provide new insight into the microevolutionary processes driving the patterns of variation.


Asunto(s)
Evolución Biológica , Variación Genética , Genética de Población , Filogenia , Selección Genética , Pájaros Cantores/anatomía & histología , Pájaros Cantores/genética , Animales , Secuencia de Bases , Teorema de Bayes , Tamaño Corporal/fisiología , Costa Rica , ADN Mitocondrial/genética , Ecuador , Flujo Génico/genética , Funciones de Verosimilitud , Modelos Lineales , Repeticiones de Microsatélite/genética , Modelos Genéticos , Datos de Secuencia Molecular , Análisis de Componente Principal , Alineación de Secuencia , Análisis de Secuencia de ADN , Pájaros Cantores/fisiología
4.
J Parasitol ; 96(2): 259-72, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19954259

RESUMEN

This study assesses the ecological factors associated with microfilariae prevalence in wild populations of endangered flightless cormorants (Phalacrocorax harrisi) and Galápagos penguins (Spheniscus mendiculus). Prevalence values were tested for correlation with a large number of environmental variables, as modeled from weather station data and measured by satellite-borne sensors. Predictions were made based on the expected effects of climatic and landscape variables on sustained populations of arthropod vectors required for transmission of microfilariae. In general, findings were consistent with predictions in both cormorants and penguins; prevalence correlated positively with temperature, precipitation, and vegetation density, and negatively with measures of environmental variability. Resulting correlates were used to derive predictive distributions of prevalence values in cormorants throughout the archipelago. Evidence is presented implicating the mosquito Aedes taeniorhynchus as a likely vector. Knowledge of environmental variables that predict risk of disease transmission by arthropod vectors may be useful in control measures should novel pathogens be introduced to the ecosystem.


Asunto(s)
Enfermedades de las Aves/epidemiología , Filariasis/veterinaria , Filarioidea/aislamiento & purificación , Spheniscidae/parasitología , Aedes/parasitología , Animales , Enfermedades de las Aves/parasitología , Enfermedades de las Aves/transmisión , Aves , Ecuador/epidemiología , Filariasis/epidemiología , Filariasis/transmisión , Filarioidea/clasificación , Filarioidea/genética , Insectos Vectores/parasitología , Microfilarias/aislamiento & purificación , Prevalencia
5.
Mol Ecol ; 9(9): 1415-9, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10972780

RESUMEN

We estimated the rate of extra-pair fertilizations (EPFs) in waved albatrosses (Phoebastria irrorata) on Isla Española, Galápagos, Ecuador, using multilocus minisatellite DNA fingerprinting. Waved albatrosses are socially monogamous, long-lived seabirds whose main population is on Española. Aggressive extra-pair copulation (EPC) attempts have been observed in the breeding colony during the days preceding egg-laying. Our genetic analyses of 16 families (single chicks and their attending parents) revealed evidence of EPFs in four families. In all cases males were the excluded parent. These data suggest that waved albatrosses have an unusually high rate of EPF relative to taxa with similar life histories. Future behavioural observations will determine the extent to which forced vs. unforced EPCs contribute to this high EPF rate.


Asunto(s)
Aves/genética , Animales , Secuencia de Bases , Aves/fisiología , Cartilla de ADN/genética , Ecuador , Femenino , Fertilización/genética , Masculino , Paternidad , Conducta Sexual Animal
6.
Heredity (Edinb) ; 77 ( Pt 6): 619-28, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8972082

RESUMEN

We used multilocus minisatellite DNA fingerprinting to examine the local genetic structure within nesting populations of green turtles (Chelonia mydas) in Tortuguero, Costa Rica and Melbourne, Florida, USA. In the Tortuguero population, there was a significant negative correlation between genetic similarity of pairs of nesting females and the distance between their nest sites both within years (r2 = 0.273; P < 0.001) and between years (r2 = 0.578; P < 0.001). Of the 122 female pairs scored for Tortuguero, 12.3 per cent had genetic similarity values resembling those of mother-offspring pairs. In the Melbourne population, however, no relationship between genetic similarity and distance was found (r2 = 0.017; P = 0.075). The distance-related genetic structure of the Tortuguero population indicates that these females exhibit low levels of dispersal from natal sites, and that nestmates return independently to nest near their natal sites. The lack of a similar structure in the Melbourne population suggests that females from this population may not return to natal sites with comparable precision. High levels of mortality among nests, hatchlings or maturing turtles produced in the Melbourne rookery may also be responsible for the absence of distance-related local genetic structure.


Asunto(s)
Tortugas/genética , Animales , Costa Rica , Dermatoglifia del ADN , Femenino , Florida , Impresión Genómica , Secuencias Repetitivas de Ácidos Nucleicos
7.
Am J Dis Child ; 143(7): 779-81, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2741846

RESUMEN

Although common in tropical regions, pyomyositis is rare in the continental United States. Fewer than 50 cases have been reported to date. It is characterized by suppuration of large muscle groups that can, if not quickly and appropriately treated, lead to sepsis and death. Diagnosis can be difficult secondary to the atypical appearance of the abscess process early on. Almost all cases have occurred in otherwise healthy people. The simultaneous occurrence of pyomyositis and immunodeficiency is rare. A recent report of a case in an adult with the acquired immunodeficiency syndrome (AIDS) is not, however, unexpected. We describe the first documented occurrence of pyomyositis in a child with AIDS. A brief review of the topic is included. Pyomyositis should be included in the list of unusual infections that can occur in children with AIDS.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/complicaciones , Miositis/complicaciones , Infecciones Estafilocócicas/complicaciones , Humanos , Lactante , Masculino , Miositis/patología , Infecciones Estafilocócicas/patología , Supuración
8.
Science ; 222(4624): 619-21, 1983 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-17843839

RESUMEN

Concentrations in Gulf of Mexico slope sediment of material soluble in methanol and benzene as high as 4.5 percent are shown to be attributable to biodegraded petroleum. Associated carbonate deposits and organic sulfur are the products of the microbial oxidation of petroleum and sulfate reduction. The results of chemical and carbon isotope analyses indicate that high concentrations of hydrocarbon gases, from methane to pentane, are petroleum rather than microbiologically derived. These hydrocarbons, believed to have been produced thermally at depth, probably reached the surface through faults and fractures associated with salt diapirs.

11.
J Pediatr ; 99(3): 360-4, 1981 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6790688

RESUMEN

We compared two feeding regimens, continuous intragastric feedings and intermittent oral feeding, in nine infants with protracted diarrhea and malnutrition and two infants with surgically created short bowel. Continuous nasogastric feeding caused significant increases in enteral balance of the major nutrients, whereas intermittent feedings resulted in negative or only slightly positive enteral balance. The improvements in enteral balance from intermittent to continuous feeding in infants with diarrhea were as follows: Fat from 13 +/- 0.8 to 22 +/- 2.0 gm/24 hours; nitrogen from 0.63 +/- 0.2 to 1.7 +/- 0.2 gm/24 hours; calcium from -63 +/- 20 to 145 +/- 4 mg/24 hours; zinc from -0.57 +/- 0.2 to 1.3 +/- 0.2 mg/24 hours; and copper from -0.09 +/- 0.03 to 0.21 +/- 0.02 mg/24 hours. There was also a significant increase in body weight during the continuous feeding (168 +/- 16 gm/72 hours) as compared to the intermittent feeding (-171 +/- 26 gm/72 hours). Similar improvements in enteral balance were seen in the two infants with short bowel. These findings document that improved enteral balance can be achieved with continuous feeding in infants with bowel disease.


Asunto(s)
Nutrición Enteral/métodos , Enfermedades Intestinales/terapia , Peso Corporal , Diarrea Infantil/terapia , Alimentos Formulados , Humanos , Lactante , Trastornos de la Nutrición del Lactante/terapia , Absorción Intestinal , Minerales/metabolismo , Nitrógeno/metabolismo
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