Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
JAMA ; 311(20): 2074-82, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24838476

RESUMEN

IMPORTANCE: Maternal smoking during pregnancy adversely affects offspring lung development, with lifelong decreases in pulmonary function and increased asthma risk. In a primate model, vitamin C blocked some of the in-utero effects of nicotine on lung development and offspring pulmonary function. OBJECTIVE: To determine if newborns of pregnant smokers randomized to receive daily vitamin C would have improved results of pulmonary function tests (PFTs) and decreased wheezing compared with those randomized to placebo. DESIGN, SETTING, AND PARTICIPANTS: Randomized, double-blind trial conducted in 3 sites in the Pacific Northwest between March 2007 and January 2011. One hundred fifty-nine newborns of randomized pregnant smokers (76 vitamin C treated and 83 placebo treated) and 76 newborns of pregnant nonsmokers were studied with newborn PFTs. Follow-up assessment including wheezing was assessed through age 1 year, and PFTs were performed at age 1 year. INTERVENTIONS: Pregnant women were randomized to receive vitamin C (500 mg/d) (n = 89) or placebo (n = 90). MAIN OUTCOMES AND MEASURES: The primary outcome was measurement of newborn pulmonary function (ratio of the time to peak tidal expiratory flow to expiratory time [TPTEF:TE] and passive respiratory compliance per kilogram [Crs/kg]) within 72 hours of age. Secondary outcomes included incidence of wheezing through age 1 year and PFT results at age 1 year. A subgroup of pregnant smokers and nonsmokers had genotyping performed. RESULTS: Newborns of women randomized to vitamin C (n = 76), compared with those randomized to placebo (n = 83), had improved pulmonary function as measured by TPTEF:TE (0.383 vs 0.345 [adjusted 95% CI for difference, 0.011-0.062]; P = .006) and Crs/kg (1.32 vs 1.20 mL/cm H2O/kg [95% CI, 0.02-0.20]; P = .01). Offspring of women randomized to vitamin C had significantly decreased wheezing through age 1 year (15/70 [21%] vs 31/77 [40%]; relative risk, 0.56 [95% CI, 0.33-0.95]; P = .03). There were no significant differences in the 1-year PFT results between the vitamin C and placebo groups. The effect of maternal smoking on newborn lung function was associated with maternal genotype for the α5 nicotinic receptor (rs16969968) (P < .001 for interaction). CONCLUSIONS AND RELEVANCE: Supplemental vitamin C taken by pregnant smokers improved newborn PFT results and decreased wheezing through 1 year in the offspring. Vitamin C in pregnant smokers may be an inexpensive and simple approach to decrease the effects of smoking in pregnancy on newborn pulmonary function and respiratory morbidities. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00632476.


Asunto(s)
Ácido Ascórbico/uso terapéutico , Pulmón/fisiopatología , Ruidos Respiratorios , Fumar/efectos adversos , Vitaminas/uso terapéutico , Adulto , Suplementos Dietéticos , Método Doble Ciego , Femenino , Humanos , Lactante , Recién Nacido , Enfermedades del Recién Nacido/prevención & control , Embarazo , Atención Prenatal , Efectos Tardíos de la Exposición Prenatal/prevención & control , Pruebas de Función Respiratoria , Ruidos Respiratorios/etiología , Ruidos Respiratorios/fisiopatología , Enfermedades Respiratorias/prevención & control , Adulto Joven
2.
J Chem Ecol ; 38(1): 81-7, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22246519

RESUMEN

Mature male African (Loxodonta africana) and Asian (Elephas maximus) elephants exhibit periodic episodes of musth, a state in which serum androgens are elevated, food intake typically decreases, aggressiveness often increases, and breeding success is enhanced. Urine is a common source of chemical signals in a variety of mammals. Elephants in musth dribble urine almost continuously for lengthy periods, suggesting that the chemicals in their urine may reveal their physiological condition to conspecifics. We investigated the volatile urinary chemicals in captive male elephants using automated solid phase dynamic extraction (SPDE) and gas chromatography-mass spectrometry (GC-MS). We found higher levels of alkan-2-ones, alkan-2-ols, and some aromatic compounds in urine from males in musth than in urine from non-musth males or from females. Levels of ketones and alcohols increased as the urine aged, likely due to microbial metabolism of fatty acids. Protein-derived aromatic metabolites also increased in abundance after urination, likely due to microbial hydrolysis of hydrophilic conjugates. We suggest that microbes may play an important role in timed release of urinary semiochemicals during elephant musth.


Asunto(s)
Bacterias , Elefantes/microbiología , Elefantes/orina , Feromonas/orina , Alcanos/química , Alcanos/orina , Animales , Conducta Animal , Centrifugación , Femenino , Masculino , Temperatura , Factores de Tiempo
3.
Mol Ecol ; 17(11): 2666-79, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18466226

RESUMEN

Nonrandom patterns of mating and dispersal create fine-scale genetic structure in natural populations - especially of social mammals - with important evolutionary and conservation genetic consequences. Such structure is well-characterized for typical mammalian societies; that is, societies where social group composition is stable, dispersal is male-biased, and males form permanent breeding associations in just one or a few social groups over the course of their lives. However, genetic structure is not well understood for social mammals that differ from this pattern, including elephants. In elephant societies, social groups fission and fuse, and males never form permanent breeding associations with female groups. Here, we combine 33 years of behavioural observations with genetic information for 545 African elephants (Loxodonta africana), to investigate how mating and dispersal behaviours structure genetic variation between social groups and across age classes. We found that, like most social mammals, female matrilocality in elephants creates co-ancestry within core social groups and significant genetic differentiation between groups (Phi(ST) = 0.058). However, unlike typical social mammals, male elephants do not bias reproduction towards a limited subset of social groups, and instead breed randomly across the population. As a result, reproductively dominant males mediate gene flow between core groups, which creates cohorts of similar-aged paternal relatives across the population. Because poaching tends to eliminate the oldest elephants from populations, illegal hunting and poaching are likely to erode fine-scale genetic structure. We discuss our results and their evolutionary and conservation genetic implications in the context of other social mammals.


Asunto(s)
Elefantes/genética , Variación Genética , Conducta Sexual Animal , Animales , Elefantes/fisiología , Femenino , Genética de Población , Genotipo , Kenia , Masculino , Repeticiones de Microsatélite/genética
4.
J Neuroimmunol ; 291: 1-10, 2016 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-26857488

RESUMEN

Japanese macaque encephalomyelitis (JME) is an inflammatory demyelinating disease that occurs spontaneously in a colony of Japanese macaques (JM) at the Oregon National Primate Research Center. Animals with JME display clinical signs resembling multiple sclerosis (MS), and magnetic resonance imaging reveals multiple T2-weighted hyperintensities and gadolinium-enhancing lesions in the central nervous system (CNS). Here we undertook studies to determine if JME possesses features of an immune-mediated disease in the CNS. Comparable to MS, the CNS of animals with JME contain active lesions positive for IL-17, CD4+ T cells with Th1 and Th17 phenotypes, CD8+ T cells, and positive CSF findings.


Asunto(s)
Sistema Nervioso Central/patología , Encefalomielitis/embriología , Encefalomielitis/patología , Esclerosis Múltiple/inmunología , Esclerosis Múltiple/patología , Animales , Antígenos CD/metabolismo , Linfocitos B/metabolismo , Linfocitos B/patología , Citocinas/metabolismo , Modelos Animales de Enfermedad , Linfocitos/metabolismo , Linfocitos/patología , Macaca , Macrófagos/metabolismo , Macrófagos/patología , Imagen por Resonancia Magnética , Proteínas de Microfilamentos/metabolismo , Microglía/metabolismo , Microglía/patología , Proteína Básica de Mielina/metabolismo , Proteínas del Tejido Nervioso/metabolismo
5.
Mol Ecol ; 16(19): 4138-48, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17784925

RESUMEN

The costs of inbreeding depression, as well as the opportunity costs of inbreeding avoidance, determine whether and which mechanisms of inbreeding avoidance evolve. In African elephants, sex-biased dispersal does not lead to the complete separation of male and female relatives, and so individuals may experience selection to recognize kin and avoid inbreeding. However, because estrous females are rare and male-male competition for mates is intense, the opportunity costs of inbreeding avoidance may be high, particularly for males. Here we combine 28 years of behavioural and demographic data on wild elephants with genotypes from 545 adult females, adult males, and calves in Amboseli National Park, Kenya, to test the hypothesis that elephants engage in sexual behaviour and reproduction with relatives less often than expected by chance. We found support for this hypothesis: males engaged in proportionally fewer sexual behaviours and sired proportionally fewer offspring with females that were natal family members or close genetic relatives (both maternal and paternal) than they did with nonkin. We discuss the relevance of these results for understanding the evolution of inbreeding avoidance and for elephant conservation.


Asunto(s)
Elefantes/fisiología , Endogamia , Conducta Sexual Animal , Animales , Elefantes/genética , Femenino , Genotipo , Kenia , Masculino
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA