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1.
Environ Sci Technol ; 53(7): 3888-3897, 2019 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-30802040

RESUMEN

Birds are potentially exposed to neonicotinoid insecticides by ingestion of coated seeds during crop planting. Adult male Japanese quail were orally dosed with wheat seeds coated with an imidacloprid (IMI) formulation at either 0.9 or 2.7 mg/kg body weight (BW) (∼3 and 9% of IMI LD50 for Japanese quail, respectively) for 1 or 10 days. Quail were euthanized between 1 and 24 h postexposure to assess toxicokinetics. Analysis revealed rapid absorption (1 h) into blood and distribution to the brain, muscle, kidney, and liver. Clearance to below detection limits occurred at both dose levels and exposure durations in all tissues within 24 h. Metabolism was extensive, with 5-OH-IMI and IMI-olefin detected at greater concentrations than IMI in tissues and fecal samples. There was no lethality or overt signs of toxicity at either dose level. Furthermore, no evidence of enhanced expression of mRNA genes associated with hepatic xenobiotic metabolism, oxidative DNA damage, or alterations in concentrations of corticosterone and thyroid hormones was observed. Application of the toxicokinetic data was used to predict IMI residue levels in the liver with reasonable results for some field exposure and avian mortality events. It would appear that some affected species of birds are either consuming larger quantities of seeds or exhibit differences in ADME or sensitivity than predicted by read-across from these data.


Asunto(s)
Coturnix , Triticum , Animales , Masculino , Neonicotinoides , Nitrocompuestos , Semillas , Toxicocinética
2.
Ecotoxicol Environ Saf ; 179: 151-159, 2019 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-31035249

RESUMEN

Tetrabromobisphenol A bis(2,3-dibromopropyl ether) (TBBPA-BDBPE) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTPBE) are both brominated flame retardants (BFRs) that have been detected in birds; however, their potential biological effects are largely unknown. We assessed the effects of embryonic exposure to TBBPA-BDBPE and BTBPE in a model avian predator, the American kestrel (Falco sparverius). Fertile eggs from a captive population of kestrels were injected on embryonic day 5 (ED5) with a vehicle control or one of three doses within the range of concentrations that have been detected in biota (nominal concentrations of 0, 10, 50 or 100 ng/g egg; measured concentrations 0, 3.0, 13.7 or 33.5 ng TBBPA-BDBPE/g egg and 0, 5.3, 26.8 or 58.1 ng BTBPE/g egg). Eggs were artificially incubated until hatching (ED28), at which point blood and tissues were collected to measure morphological and physiological endpoints, including organ somatic indices, circulating and glandular thyroid hormone concentrations, thyroid gland histology, hepatic deiodinase activity, and markers of oxidative stress. Neither compound had any effects on embryo survival through 90% of the incubation period or on hatching success, body mass, organ size, or oxidative stress of hatchlings. There was evidence of sex-specific effects in the thyroid system responses to the BTBPE exposures, with type 2 deiodinase (D2) activity decreasing at higher doses in female, but not in male hatchlings, suggesting that females may be more sensitive to BTBPE. However, there were no effects of TBBPA-BDBPE on the thyroid system in kestrels. For the BTPBE study, a subset of high-dose eggs was collected throughout the incubation period to measure changes in BTBPE concentrations. There was no decrease in BTBPE over the incubation period, suggesting that BTBPE is slowly metabolized by kestrel embryos throughout their ∼28-d development. These two compounds, therefore, do not appear to be particularly toxic to embryos of the American kestrel.


Asunto(s)
Bromobencenos/toxicidad , Desarrollo Embrionario/efectos de los fármacos , Contaminantes Ambientales/toxicidad , Falconiformes/crecimiento & desarrollo , Retardadores de Llama/toxicidad , Óvulo/efectos de los fármacos , Bifenilos Polibrominados/toxicidad , Animales , Relación Dosis-Respuesta a Droga , Desarrollo Embrionario/fisiología , Falconiformes/metabolismo , Femenino , Yoduro Peroxidasa/metabolismo , Hígado/efectos de los fármacos , Hígado/enzimología , Masculino , Tamaño de los Órganos/efectos de los fármacos , Óvulo/metabolismo , Estrés Oxidativo/efectos de los fármacos , Glándula Tiroides/efectos de los fármacos , Glándula Tiroides/metabolismo , Glándula Tiroides/patología , Hormonas Tiroideas/metabolismo
3.
Arch Environ Contam Toxicol ; 77(1): 1-13, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30955057

RESUMEN

A site in northeastern Michigan, Oscoda Township, has some of the highest recorded exposure in birds to perfluorinated substances (PFASs) in the United States. Some egg and plasma concentrations at that location exceeded the lowest reproductive effect threshold established for two avian laboratory species. The objectives of this study were to determine whether there were reproductive effects or physiological responses in a model bird species, the tree swallow (Tachycineta bicolor), associated with this extremely high exposure to PFASs. The lack of exposure above background to other contaminants at this site allowed for an assessment of PFAS effects without the complication that responses may be caused by other contaminants. A secondary objective was to determine the distribution of PFASs in multiple tissue types to better understand and interpret residues in different tissues. This can best be done at highly exposed locations where tissue concentrations would be expected to be above detectable levels if they are present in that tissue. There were no demonstrable effects of PFAS exposure on reproduction nor on most physiological responses.


Asunto(s)
Contaminantes Ambientales/toxicidad , Fluorocarburos/toxicidad , Comportamiento de Nidificación/efectos de los fármacos , Golondrinas/fisiología , Animales , Monitoreo del Ambiente , Michigan , Reproducción/efectos de los fármacos
4.
Environ Monit Assess ; 190(2): 104, 2018 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-29380143

RESUMEN

Biomarker responses and histopathological lesions have been documented in laboratory mammals exposed to elevated concentrations of lead and cadmium. The exposure of white-footed mice (Peromyscus leucopus) to these metals and the potential associated toxic effects were examined at three contaminated sites in the Southeast Missouri Lead Mining District and at a reference site in MO, USA. Mice from the contaminated sites showed evidence of oxidative stress and reduced activity of red blood cell δ-aminolevulinic acid dehydratase (ALAD). Histological examinations of the liver and kidney, cytologic examination of blood smears, and biomarkers of lipid peroxidation and DNA damage failed to show indications of toxic effects from lead. The biomagnification factor of cadmium (hepatic concentration/soil concentration) at a site with a strongly acid soil was 44 times the average of the biomagnification factors at two sites with slightly alkaline soils. The elevated concentrations of cadmium in the mice did not cause observable toxicity, but were associated with about a 50% decrease in expected tissue lead concentrations and greater ALAD activity compared to the activity at the reference site. Lead was associated with a decrease in concentrations of hepatic glutathione and thiols, whereas cadmium was associated with an increase. In addition, to support risk assessment efforts, we developed linear regression models relating both tissue lead dosages (based on a previously published a laboratory study) and tissue lead concentrations in Peromyscus to soil lead concentrations.


Asunto(s)
Cadmio/metabolismo , Monitoreo del Ambiente , Plomo/metabolismo , Peromyscus/fisiología , Animales , Biomarcadores/metabolismo , Cadmio/análisis , Cadmio/toxicidad , Plomo/análisis , Plomo/toxicidad , Hígado/química , Ratones , Minería , Missouri , Porfobilinógeno Sintasa
5.
Ecotoxicology ; 26(10): 1392-1407, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29039061

RESUMEN

Tree swallow, Tachycineta bicolor, nestlings were collected from 60 sites in the Great Lakes, which included multiple sites within 27 Areas of Concern (AOCs) and six sites not listed as AOCs from 2010 to 2014. Nestlings, approximately 12 days-of-age, were evaluated for ethoxyresorufin-O-dealkylase (EROD) activity, chromosomal damage, and six measures of oxidative stress. Data on each of these biomarkers were divided into four equal numbered groups from the highest to lowest values and the groups were compared to contaminant concentrations using multivariate analysis. Contaminant concentrations, from the same nestlings, included polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), perfluorinated compounds (PFCs), and 17 elements. Alkylated polycyclic aromatic hydrocarbons (aPAHs) and parent PAHs (pPAHs) were measured in pooled nestling dietary samples. Polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and pesticides were measured in sibling eggs. Concentrations of aPAHs, pPAHs, chlordane, dieldrin, heptachlor, and PCBs, in that order, were the major contributors to the significant differences between the lowest and highest EROD activities; PFCs, PBDEs, the remaining pesticides, and all elements were of secondary importance. The four categories of chromosomal damage did not separate out well based on the contaminants measured. Concentrations of aPAHs, pPAHs, heptachlor, PCBs, chlordane, and dieldrin were the major contributors to the significant differences between the lowest and highest activities of two oxidative stress measures, total sulfhydryl (TSH) activity and protein bound sulfhydryl (PBSH) activity. The four categories of thiobarbituric acid reacting substances (TBARS), oxidized glutathione (GSSG), reduced glutathione (GSH), and the ratio of GSSG/GSH did not separate well based on the contaminants measured.


Asunto(s)
Citocromo P-450 CYP1A1/metabolismo , Monitoreo del Ambiente , Contaminantes Ambientales/toxicidad , Estrés Oxidativo , Golondrinas/fisiología , Animales , Aberraciones Cromosómicas/inducido químicamente , Contaminantes Ambientales/metabolismo , Great Lakes Region , Éteres Difenilos Halogenados/metabolismo , Éteres Difenilos Halogenados/toxicidad , Plaguicidas/metabolismo , Plaguicidas/toxicidad , Bifenilos Policlorados/metabolismo , Bifenilos Policlorados/toxicidad , Dibenzodioxinas Policloradas/metabolismo , Dibenzodioxinas Policloradas/toxicidad , Hidrocarburos Policíclicos Aromáticos/metabolismo , Hidrocarburos Policíclicos Aromáticos/toxicidad
6.
Environ Sci Technol ; 49(12): 7448-55, 2015 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-25988605

RESUMEN

Organophosphate triesters are high production volume additive flame retardants (OPFRs) and plasticizers. Shown to accumulate in abiotic and biotic environmental compartments, little is known about the risks they pose. Captive adult male American kestrels (Falco sparverius) were fed the same dose (22 ng OPFR/g kestrel/d) daily (21 d) of tris(2-butoxyethyl) phosphate (TBOEP), tris(2-chloroethyl) phosphate (TCEP), tris(2-chloroisopropyl) phosphate (TCIPP), or tris(1,2-dichloro-2-propyl) phosphate (TDCIPP). Concentrations were undetected in tissues (renal, hepatic), suggesting rapid metabolism. There were no changes in glutathione status, indicators of hepatic oxidative status, or the cholinergic system (i.e., cerebrum, plasma cholinesterases; cerebrum muscarinic, nicotinic receptors). Modest changes occurred in hepatocyte integrity and function (clinical chemistry). Significant effects on plasma free triiodothyronine (FT3) concentrations occurred with exposure to TBOEP, TCEP, TCIPP, and TDCIPP; TBOEP and TCEP had additional overall effects on free thyroxine (FT4), whereas TDCIPP also influenced total thyroxine (TT4). Relative increases (32%-96%) in circulating FT3, TT3, FT4, and/or TT4 were variable with each OPFR at 7 d exposure, but limited thereafter, which was likely maintained through decreased thyroid gland activity and increased hepatic deiodinase activity. The observed physiological and endocrine effects occurred at environmentally relevant concentrations and suggest parent OPFRs or metabolites may have been present despite rapid degradation.


Asunto(s)
Dieta , Sistema Endocrino/metabolismo , Exposición a Riesgos Ambientales/análisis , Falconiformes/fisiología , Retardadores de Llama/toxicidad , Compuestos Organofosforados/toxicidad , Animales , Sistema Endocrino/efectos de los fármacos , Falconiformes/sangre , Masculino , Hormonas Tiroideas/sangre , Estados Unidos
7.
Ecotoxicology ; 24(5): 1028-39, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25777616

RESUMEN

The health of tree swallows, Tachycineta bicolor, on the Upper Mississippi River (UMR) was assessed in 2010 and 2011 using biomarkers at six sites downriver of Minneapolis/St. Paul, MN metropolitan area, a tributary into the UMR, and a nearby lake. Chromosomal damage was evaluated in nestling blood by measuring the coefficient of variation of DNA content (DNA CV) using flow cytometry. Cytochrome P450 1A activity in nestling liver was measured using the ethoxyresorufin-O-dealkylase (EROD) assay, and oxidative stress was estimated in nestling livers via determination of thiobarbituric acid reacting substances (TBARS), reduced glutathione (GSH), oxidized glutathione (GSSG), the ratio GSSG/GSH, total sulfhydryl, and protein bound sulfhydryl (PBSH). A multilevel regression model (DNA CV) and simple regressions (EROD and oxidative stress) were used to evaluate biomarker responses for each location. Chromosomal damage was significantly elevated at two sites on the UMR (Pigs Eye and Pool 2) relative to the Green Mountain Lake reference site, while the induction of EROD activity was only observed at Pigs Eye. No measures of oxidative stress differed among sites. Multivariate analysis confirmed an increased DNA CV at Pigs Eye and Pool 2, and elevated EROD activity at Pigs Eye. These results suggest that the health of tree swallows has been altered at the DNA level at Pigs Eye and Pool 2 sites, and at the physiological level at Pigs Eye site only.


Asunto(s)
Citocromo P-450 CYP1A1/metabolismo , Daño del ADN/genética , Estrés Oxidativo/fisiología , Golondrinas/genética , Animales , Biomarcadores/metabolismo , Citometría de Flujo , Hígado/metabolismo , Minnesota , Análisis Multivariante , Análisis de Regresión , Ríos , Golondrinas/fisiología
8.
Ecotoxicology ; 24(4): 720-34, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25600128

RESUMEN

Despite widespread use and benefit, there are growing concerns regarding hazards of second-generation anticoagulant rodenticides to non-target wildlife which may result in expanded use of first-generation compounds, including chlorophacinone (CPN). The toxicity of CPN over a 7-day exposure period was investigated in American kestrels (Falco sparverius) fed either rat tissue mechanically-amended with CPN, tissue from rats fed Rozol(®) bait (biologically-incorporated CPN), or control diets (tissue from untreated rats or commercial bird of prey diet) ad libitum. Nominal CPN concentrations in the formulated diets were 0.15, 0.75 and 1.5 µg/g food wet weight, and measured concentrations averaged 94 % of target values. Kestrel food consumption was similar among groups and body weight varied by less than 6 %. Overt signs of intoxication, liver CPN residues, and changes in prothrombin time (PT), Russell's viper venom time (RVVT) and hematocrit, were generally dose-dependent. Histological evidence of hemorrhage was present at all CPN dose levels, and most frequently observed in pectoral muscle and heart. There were no apparent differences in toxicity between mechanically-amended and biologically-incorporated CPN diet formulations. Dietary-based toxicity reference values at which clotting times were prolonged in 50 % of the kestrels were 79.2 µg CPN consumed/kg body weight-day for PT and 39.1 µg/kg body weight-day for RVVT. Based upon daily food consumption of kestrels and previously reported CPN concentrations found in small mammals following field baiting trials, these toxicity reference values might be exceeded by free-ranging raptors consuming such exposed prey. Tissue-based toxicity reference values for coagulopathy in 50 % of exposed birds were 0.107 µg CPN/g liver wet weight for PT and 0.076 µg/g liver for RVVT, and are below the range of residue levels reported in raptor mortality incidents attributed to CPN exposure. Sublethal responses associated with exposure to environmentally realistic concentrations of CPN could compromise survival of free-ranging raptors, and should be considered in weighing the costs and benefits of anticoagulant rodenticide use in pest control and eradication programs.


Asunto(s)
Anticoagulantes/toxicidad , Coagulación Sanguínea/efectos de los fármacos , Falconiformes/metabolismo , Indanos/toxicidad , Rodenticidas/toxicidad , Animales , Hígado/efectos de los fármacos , Masculino , Valores de Referencia , Riesgo , Medición de Riesgo
9.
Environ Toxicol Chem ; 43(4): 856-877, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38376364

RESUMEN

Legacy contaminants and contaminants of emerging concern (CECs) were assessed in tree swallow (Tachycineta bicolor) tissue and diet samples from three drainages in the Milwaukee estuary, Wisconsin, USA, to understand exposures and possible biomarker responses. Two remote Wisconsin lakes were assessed for comparative purposes. Bioaccumulative classes of contaminants, such as polybrominated diphenyl ethers and per- and polyfluoroalkyl substances, while at higher concentrations than the reference lakes, did not vary significantly among sites or among the three drainages. Polycyclic aromatic hydrocarbons were assessed in diet and sediment and were from primarily pyrogenic sources. Ten biomarkers were assessed relative to contaminant exposure. Polychlorinated biphenyls (PCBs) were elevated above reference conditions at all Milwaukee sites but did not correlate with any measured biomarker responses. Only one site, Cedarburg, just downstream from a Superfund site, had elevated PCBs compared to other sites in the Milwaukee estuary. Few non-organochlorine insecticides or herbicides were detected in tree swallow liver tissue, except for the atrazine metabolite desethylatrazine. Few pharmaceuticals and personal care products were detected in liver tissue except for N,N-diethyl-meta-toluamide, iopamidol, and two antibiotics. The present study is one of the most comprehensive assessments to date, along with the previously published Maumee River data, on the exposure and effects of a wide variety of CECs in birds. Environ Toxicol Chem 2024;43:856-877. © 2024 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.


Asunto(s)
Bifenilos Policlorados , Golondrinas , Animales , Humanos , Bifenilos Policlorados/análisis , Wisconsin , Monitoreo del Ambiente , Estuarios , Golondrinas/metabolismo , DEET , Biomarcadores/metabolismo
10.
Environ Int ; 157: 106826, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34438233

RESUMEN

Brominated flame retardant chemicals, such as 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EHTBB) (CAS #: 183658-27-7) and bis(2-ethylhexyl)-2,3,4,5-tetrabromophthalate (TBPH) (CAS #: 26040-51-7), have been detected in avian tissues and eggs from remote regions. Exposure to EHTBB and TBPH has been shown to cause oxidative stress and altered thyroid function in rodents and fish, yet no controlled studies have examined potential adverse effects of exposure in birds. Because flame retardants have been detected in wild raptors, we used American kestrels (Falco sparverius) as a model raptor to determine whether in ovo exposure to EHTBB or TBPH affected growth, hatching success, oxidative stress, or thyroid function. We exposed kestrel embryos to nominal concentrations (10, 50, or 100 ng g-1 egg weight) of EHTBB and TBPH via egg-injection on embryonic day 5. Embryonic exposure (~23 d) to EHTBB increased thyroid gland mass, reduced glandular colloid and total thyroxine (T4) in hatchling males and females, whereas deiodinase enzyme activity increased in males but decreased in females. Hatchlings exposed to TBPH in ovo exhibited reduced colloid and increased oxidative stress. Although exposure to EHTBB and TBPH caused several physiological effects (e.g., heart and brain mass), only exposure to 50 ng g-1 EHTBB appeared to reduce hatching success. Our results suggest these flame retardants may be hazardous for predatory birds. Future research should evaluate long-term survival and fitness consequences in birds exposed to these chemicals.


Asunto(s)
Falconiformes , Retardadores de Llama , Animales , Femenino , Retardadores de Llama/toxicidad , Masculino , Estrés Oxidativo , Glándula Tiroides , Tiroxina/toxicidad
11.
Environ Toxicol Chem ; 39(10): 1936-1952, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32495340

RESUMEN

Exposure to multiple classes of contaminants, both legacy and contaminants of emerging concern (CECs), were assessed in tree swallow (Tachycineta bicolor) tissue and diet samples from 6 sites along the Maumee River, Ohio, USA, to understand both exposure and possible effects of exposure to those CECs for which there are little avian data. The 6 sites represented a gradient from intensive agriculture upstream to highly urbanized and industrial landscapes downstream; 1 or 2 remote Wisconsin lakes were assessed for comparative purposes. Cytochrome P450 induction, DNA damage, and thyroid function were also assessed relative to contaminant exposure. Bioaccumulative CECs, such as polybrominated diphenyl ethers (PBDEs) and perfluorinated substances, did not follow any upstream to downstream gradient; but both had significantly greater concentrations along the Maumee River than at the remote lake sites. Greater exposure to PBDEs was apparent in swallows at or near wastewater-treatment facilities than at other sites. Total polychlorinated biphenyl and total polycyclic aromatic hydrocarbon concentrations were greater in swallows at downstream locations compared to upstream sites and were associated with higher ethoxyresorufin-O-dealkylase activity. Few herbicides or nonorganochlorine insecticides were detected in swallow tissues or their food, except for atrazine and its metabolite desethylatrazine. Few pharmaceuticals and personal care products were detected except for DEET and iopamidol. Both were detected in most liver samples but not in eggs, as well as detected at the remote lake sites. This is one of the most comprehensive assessments to date of exposure and effects of a wide variety of CECs in birds. Environ Toxicol Chem 2020;39:1936-1952. © 2020 SETAC. This article has been contributed to by US Government employees and their work is in the public domain in the USA.


Asunto(s)
Monitoreo del Ambiente/métodos , Hidrocarburos Aromáticos/análisis , Ríos/química , Golondrinas/metabolismo , Contaminantes Químicos del Agua/análisis , Agricultura , Animales , Cosméticos/análisis , Cosméticos/metabolismo , Éteres Difenilos Halogenados/análisis , Éteres Difenilos Halogenados/metabolismo , Hidrocarburos Aromáticos/metabolismo , Industrias , Lagos/química , Ohio , Bifenilos Policlorados/análisis , Bifenilos Policlorados/metabolismo , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/metabolismo , Urbanización , Aguas Residuales/química , Contaminantes Químicos del Agua/metabolismo , Wisconsin
12.
Environ Pollut ; 259: 113813, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31896481

RESUMEN

Arsenic (As) is broadly distributed due to natural and anthropogenic sources, and it may cause adverse effects in birds. However, research on other elements (Pb, Hg and Cd) has been prioritized, resulting in scarce data on As exposure and related effects in wild birds. One of the mechanisms responsible for As toxicity is oxidative stress. Therefore, the aim of this study was to investigate if environmentally relevant As levels affected oxidative stress biomarkers in great tits (Parus major). This is the first field experiment studying the effects of As on oxidative stress in wild passerines. Wild great tit nestlings were orally dosed with sodium arsenite (Control: water, Low dose: 0.2 µg g-1 d-1 and High dose: 1 µg g-1 d-1; from day 3 to day 13 post-hatching). We intended to reach As concentrations similar to those at which passerines are exposed to at actual polluted areas. We compared the responses to the experimental manipulations (High, Low and Control groups) with those in an As/metal-exposed population breeding close to a Cu-Ni smelter in Finland (Smelter group). A set of antioxidants (tGSH, GSH:GSSG ratio, CAT, SOD, GST and GPx), and oxidative damage biomarkers (lipid peroxidation, protein carbonylation, 8-hydroxy-2'-deoxyguanosine formation in DNA, and telomere length) were explored in blood. Arsenic administration had no significant effect on most of the biomarkers measured: only the CAT activity was lower in the High As group and the GPx activity was enhanced in the Smelter group compared to the Control. Our results suggest that the dose and duration of the As exposure was not enough to induce oxidative damage in red cells of great tit nestlings. In spite of this, nestlings dosed with 1 µg g-1 d-1 of sodium arsenite showed non-significantly higher oxidative stress biomarkers than controls, suggesting that we were close to an effect level for the redox-defense system. Oxidative effects at equivalent As levels combined with other stressors cannot be dismissed.


Asunto(s)
Arsénico/toxicidad , Contaminantes Ambientales/toxicidad , Passeriformes , Animales , Antioxidantes , Finlandia , Estrés Oxidativo/fisiología
13.
Int J Comput Assist Radiol Surg ; 14(3): 451-461, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30542975

RESUMEN

PURPOSE: Pathology detection in medical image data is an important but a rather complicated task. In particular, the big variability of the pathologies is a challenge to automatic detection methods and even to machine learning methods. Supervised algorithms would usually learn the appearance of a single pathological structure based on a large annotated dataset. As such data is not usually available, especially in large amounts, in this work we pursue a different unsupervised approach. METHODS: Our method is based on learning the entire variability of healthy data and detect pathologies by their differences to the learned norm. For this purpose, we use conditional variational autoencoders which learn the reconstruction and encoding distribution of healthy images and also have the ability to integrate certain prior knowledge about the data (condition). RESULTS: Our experiments on different 2D and 3D datasets show that the approach is suitable for the detection of pathologies and deliver reasonable Dice coefficients and AUCs. Also this method can estimate missing correspondences in pathological images and thus can be used as a pre-step to a registration method. Our experiments show improving registration results on pathological data when using this approach. CONCLUSIONS: Overall the presented approach is suitable for a rough pathology detection in medical images and can be successfully used as a preprocessing step to other image processing methods.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Aprendizaje Automático , Patología/métodos , Algoritmos , Área Bajo la Curva , Neoplasias Encefálicas/diagnóstico por imagen , Glioblastoma/diagnóstico por imagen , Humanos , Imagenología Tridimensional/métodos , Pulmón/diagnóstico por imagen , Fantasmas de Imagen
14.
Clin Pediatr (Phila) ; 57(8): 937-944, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29082772

RESUMEN

OBJECTIVE: To identify clinical and psychosocial factors associated with patient experience with care. METHODS: We analyzed patient experience surveys, corresponding clinical and psychosocial the data of 1567 encounters using survey-weighted multivariate logistic regression analysis with willingness to recommend the facility as outcome variable. RESULTS: Parents are less likely to recommend the facility if there were custody issues with the child during their stay, if the child has history of chronic medical condition, and if the child is male with odds ratio and corresponding 95% confidence interval of 0.38 [0.21, 0.69], 0.43 [0.24, 0.80], and 0.67 [0.45, 0.99] respectively. Parents of older patients (1-year difference) and parents of low socioeconomic status are more likely to recommend the facility (1.05 [1.01, 1.09] and 2.74 [1.72, 4.37] respectively). CONCLUSIONS: Clinical and psychosocial factors significantly affect patient experience scores together with parent perception of provider-family communication and relationship, and hospital environment conducive for children.


Asunto(s)
Actitud del Personal de Salud , Evaluación de Resultado en la Atención de Salud , Padres/psicología , Pediatría/normas , California , Niño , Preescolar , Femenino , Encuestas de Atención de la Salud , Hospitalización/estadística & datos numéricos , Hospitales Pediátricos , Humanos , Modelos Logísticos , Masculino , Análisis Multivariante , Relaciones Enfermero-Paciente , Atención al Paciente , Pediatría/tendencias , Relaciones Médico-Paciente , Psicología , Estudios Retrospectivos , Medición de Riesgo , Resultado del Tratamiento
15.
Med Sci Sports Exerc ; 37(10): 1774-84, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16260980

RESUMEN

PURPOSE: To examine relationships between selected sociodemographic, health-related and environmental factors and levels of physical activity in older adults across three age groups. METHODS: Seven hundred sixty-four older adults (mean age = 77.4 +/- 8.6 yr) from a midsize Canadian city completed a self-administered questionnaire under researcher supervision. Level of physical activity was determined using the Physical Activity Scale for the Elderly (PASE). Correlates of physical activity were examined using previously validated questionnaires. The findings pertaining to personal and environmental factors are presented. RESULTS: Overall, significantly higher mean PASE scores were seen in those individuals in the following categories: male (P < 0.001), married or common-law (P < 0.001), not living alone (P < 0.001), not living in senior's housing (P < 0.001), higher levels of education (P < 0.001) and higher incomes (P < 0.001). Better physical health showed significant positive associations (P < 0.001) with PASE score. Individuals reporting at least four or more chronic health conditions had significantly lower PASE scores than those reporting no chronic conditions (P < 0.001). Significantly lower PASE scores were also reported in those using domestic services (P < 0.001). Higher PASE scores were related to the presence of hills, biking and walking trails, street lights, various recreation facilities, seeing others active and unattended dogs (P < 0.001 to P < 0.05). CONCLUSION: An understanding of the factors that influence physical activity behavior in older adults is critical to developing effective intervention strategies that will address the problem of physical inactivity in this population, and in doing so, improve the health status and quality of life of the older adult, while having a significant impact on healthcare expenditures.


Asunto(s)
Aptitud Física , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Evaluación Geriátrica , Estado de Salud , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida
16.
Environ Pollut ; 205: 278-90, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26114899

RESUMEN

The last large-scale ecotoxicological study of ospreys (Pandion haliaetus) in Chesapeake Bay was conducted in 2000-2001 and focused on U.S. EPA-designated Regions of Concern (ROCs; Baltimore Harbor/Patapsco, Anacostia/middle Potomac, and Elizabeth Rivers). In 2011-2012, ROCs were re-evaluated to determine spatial and temporal trends in productivity and contaminants. Concentrations of p,p'-DDE were low in eggs and below the threshold associated with eggshell thinning. Eggs from the Anacostia/middle Potomac Rivers had lower total PCB concentrations in 2011 than in 2000; however, concentrations remained unchanged in Baltimore Harbor. Polybrominated diphenyl ether flame retardants declined by 40%, and five alternative brominated flame retardants were detected at low levels. Osprey productivity was adequate to sustain local populations, and there was no relation between productivity and halogenated contaminants. Our findings document continued recovery of the osprey population, declining levels of many persistent halogenated compounds, and modest evidence of genetic damage in nestlings from industrialized regions.


Asunto(s)
Exposición a Riesgos Ambientales , Contaminantes Ambientales/toxicidad , Falconiformes/fisiología , Reproducción/efectos de los fármacos , Animales , Bahías , District of Columbia , Monitoreo del Ambiente , Contaminantes Ambientales/sangre , Contaminantes Ambientales/metabolismo , Cadena Alimentaria , Maryland , Óvulo/química , Factores de Tiempo , Virginia
17.
Rev. baiana enferm ; 34: e35995, 2020. tab
Artículo en Portugués | BDENF - enfermagem (Brasil), LILACS | ID: biblio-1115320

RESUMEN

Objetivo avaliar a intervenção educativa de enfermagem para a promoção da autoeficácia em amamentação em nutrizes internadas em uma maternidade do Norte do Brasil. Método estudo quase experimental, longitudinal, composto por um grupo de intervenção (n=80) e observacional (n=78). A intervenção educativa deu-se mediante roda de conversa. A coleta de dados ocorreu no período de janeiro a março de 2018. Resultados no grupo de intervenção as nutrizes apresentaram alta eficácia para a amamentação, enquanto que no grupo de observação encontrou-se moderada eficácia. Entre as nutrizes com maior escolaridade, que trabalham fora de casa e tinham mamilos íntegros, a intervenção educativa influenciou para melhor autoeficácia na amamentação. O grupo de intervenção apresentou média mais elevada para autoeficácia na amamentação e maior frequência de aleitamento materno exclusivo. Conclusão nas nutrizes internadas na maternidade estudada, a intervenção educativa influenciou para a manutenção da amamentação exclusiva nos 60° primeiros dias após o parto.


Objetivo evaluar la intervención educativa de enfermería para la promoción de la autoeficacia en amamantamiento en las madres lactantes en una maternidad del Norte de Brasil. Método un estudio cuasi-experimental, longitudinal, compuesto por un grupo de intervención (n=80) y un grupo observacional (n=78). La intervención educativa ocurrió a través de rueda de conversación. La recogida de datos se produjo en el período de enero a marzo de 2018. Resultados en el grupo de intervención, las madres lactantes mostraron una alta eficacia en amamantamiento, mientras que en el grupo observacional, la autoeficacia fue moderada. Entre las madres con mayor escolaridad, que trabajan fuera del hogar y con los pezones intactos, la intervención educativa influenció para una mejor autoeficacia en el amamantamiento. El grupo de intervención mostró mayor promedio para la autoeficacia en el amamantamiento y frecuencia aumentada del amamantamiento. Conclusión para las madres lactantes en la maternidad estudiada, la intervención educativa influenció el mantenimiento del amamantamiento exclusivo en los 60 primeros días después del parto.


Objective to evaluate the nursing educational intervention for the promotion of the breastfeeding self-efficacy of nursing mothers hospitalized in a maternity hospital in northern Brazil. Method quasi-experimental, longitudinal study, composed of an intervention group (n=80) and observation group (n=78). The educative intervention occurred through conversation wheel. Data collection occurred in the period from January to March 2018. Results in the intervention group, nursing mothers showed high breastfeeding efficacy, whereas in the observation group, the efficacy was moderate. Among nursing mothers with more schooling, who work out of home and with intact nipples, the educative intervention influenced for better breastfeeding self-efficacy. The intervention group showed higher mean breastfeeding self-efficacy and increased frequency of breastfeeding. Conclusion for the nursing mothers hospitalized in the maternity of study, the educative intervention influenced for the maintenance of exclusive breastfeeding within the 60 first days after delivery.


Asunto(s)
Humanos , Femenino , Embarazo , Lactancia Materna , Educación en Salud , Enfermería Maternoinfantil , Servicios de Salud Materno-Infantil , Salud Materno-Infantil
18.
Chemosphere ; 93(2): 441-7, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23769465

RESUMEN

Concentrations of polybrominated diphenyl ethers (PBDEs) in Forster's tern (Sterna forsteri) eggs from San Francisco Bay have been reported to range up to 63µgg(-1) lipid weight. This value exceeds the lowest-observed-adverse-effect level (1.8µgg(-1) egg wet weight; ∼32µg(-1) lipid weight) reported in an embryotoxicity study with American kestrels (Falco sparverius). As a surrogate for Forster's terns, common tern (Sterna hirundo) eggs were treated by air cell injection with corn oil vehicle (control) or a commercial penta-BDE formulation (DE-71) at nominal concentrations of 0.2, 2, and 20µgg(-1) egg. As a positive control, kestrel eggs received vehicle or 20µg DE-71g(-1) egg. In terns, there were no effects of DE-71 on embryonic survival, and pipping or hatching success; however, treated eggs hatched later (0.44d) than controls. Organ weights, organ-to-body weight ratios, and bone lengths did not differ, and histopathological observations were unremarkable. Several measures of hepatic oxidative stress in hatchling terns were not affected by DE-71, although there was some evidence of oxidative DNA damage (8-hydroxy-deoxyguanosine; 8-OH-dG). Although DE-71 did not impair pipping and hatching of kestrels, it did result in a delay in hatch, shorter humerus length, and reduced total thyroid weight. Concentrations of oxidized glutathione, reduced glutathione, thiobarbituric acid reactive substances, and 8-OH-dG in liver were greater in DE-71-treated kestrels compared to controls. Our findings suggest common tern embryos, and perhaps other tern species, are less sensitive to PBDEs than kestrel embryos.


Asunto(s)
Charadriiformes/embriología , Falconiformes/embriología , Bifenilos Polibrominados/toxicidad , Teratógenos/toxicidad , Animales , Huesos/efectos de los fármacos , Huesos/embriología , Charadriiformes/genética , Charadriiformes/crecimiento & desarrollo , Charadriiformes/metabolismo , Daño del ADN , Falconiformes/genética , Falconiformes/crecimiento & desarrollo , Falconiformes/metabolismo , Tamaño de los Órganos/efectos de los fármacos , Oviposición/efectos de los fármacos , Óvulo/efectos de los fármacos , Óvulo/fisiología , Estrés Oxidativo/efectos de los fármacos , Especificidad de la Especie
19.
J Appl Biomech ; 22(3): 177-85, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17215549

RESUMEN

Although leg spring stiffness represents active muscular recruitment of the lower extremity during dynamic tasks such as hopping and running, the joint-specific characteristics comprising the damping portion of this measure, leg impedance, are uncertain. The purpose of this investigation was to assess the relationship between leg impedance and energy absorption at the ankle, knee, and hip during early (impact) and late (stabilization) phases of landing. Twenty highly trained female dancers (age = 20.3 +/- 1.4 years, height = 163.7 +/- 6.0 cm, mass = 62.1 +/- 8.1 kg) were instrumented for biomechanical analysis. Subjects performed three sets of double-leg landings from under preferred, stiff, and soft landing conditions. A stepwise linear regression analysis revealed that ankle and knee energy absorption at impact, and knee and hip energy absorption during the stabilization phases of landing explained 75.5% of the variance in leg impedance. The primary predictor of leg impedance was knee energy absorption during the stabilization phase, independently accounting for 55% of the variance. Future validation studies applying this regression model to other groups of individuals are warranted.


Asunto(s)
Baile/fisiología , Transferencia de Energía/fisiología , Articulación de la Rodilla/fisiología , Pierna/fisiología , Modelos Biológicos , Movimiento/fisiología , Adulto , Simulación por Computador , Elasticidad , Femenino , Humanos , Estrés Mecánico , Viscosidad
20.
Semina ciênc. agrar ; 27(4): 515-524, out.-dez. 2006. ilus, tab
Artículo en Portugués | LILACS | ID: lil-464855

RESUMEN

Com a prática da irrigação e novos híbridos de couve-flor, é possível produzir durante todo o ano e com alta produtividade. Mas, a cultura tem sido afetada por doenças a exemplo da podridão negra causada por Xanthomonas campestris pv. campestris, fomentando novas pesquisas para seu controle. Com o objetivo de verificar o potencial de Mikania glomerata no controle dessa doença, a tintura etanólica 50 ºGL dessa planta medicinal foi avaliada quanto: atividade antimicrobiana in vitro através do crescimento bacteriano em tubos de ensaio contendo 100, 250, 500 e 1000 mg L-1 da tintura; indução de resistência local ou sistêmica em planta de couve-flor aos 25 dias de idade, em casa de vegetação, através da pulverização de tintura concomitantemente e três dias antes da inoculação com o patógeno, sendo água e calda bordaleza tratamentos controle; atividade de peroxidases em folhas tratadas e não tratadas de couve-flor, colhidas concomitantemente e as 24, 48, 72 h da pulverização da tintura e, após pulverização-inoculção. A tintura etanólica, in vitro, promoveu inibição no crescimento bacteriano, a partir da concentração de 250 mg L-1. Nas concentrações de 500 mg L-1 e 1000 mg L-1 foram observadas, respectivamente, 24 e 38 de inibição do crescimento bacteriano. Nas plantas de couve-flor foi observada redução da doença apenas em folhas tratadas com 100 e 500 mg L-1 de tintura, aplicada concomitantemente à inoculação, comportamento este semelhante ao da calda bordaleza, indicando que o controle através da tintura de guaco é através de atividade antimicrobiana direta. Ficou indicado que a indução de peroxidases ocorreu devido ao processo infeccioso e não em função dos tratamentos com tintura etanólica de guaco. Estes resultados indicam o potencial da tintura de guaco para o controle preventivo da podridão negra da couve-flor.


With the use of irrigation and new hybrids of cauliflower, it is possible to get production during all theyear with hight yield. However, the crop has been affected by diseases, as the dark rot caused by X.campestris pv. campestris. The objective of this research work was to study the potential of Mikaniaglomerata for the control of this disease. Alcoholic extract 50 ºGL of M. glomerata was evaluatedregarding to: in vitro antimicrobial activity through bacterial growth in 100, 250, 500 and 1000 mg L-1 ofthe alcoholic extract; induction of local or systemic resistance in 25 days old cauliflower, with spray ofalcoholic extract concomitantly and three days before the inoculation with the pathogen (water andbordeau mixture were used as control); peroxidases activity in leaves of cauliflower treated and nottreated, and harvested concomitantly, 24, 48 and 72 hours after spraying the alcoholic extract and alsoafter inoculation. The alcoholic extract of M. glomerata showed inhibition of the bacterial growth invitro at the concentrations of 250, 500 and 1000 mg L-1. The concentrations of 500 mg L-1 and 1000 mg L-1inhibited 24% and 38% of the bacterial growth. This inhibition could be due to antibacterial compoundsin the alcoholic extract. An inhibition of the disease in vivo occurred only in the leaves treated with 100and 500 mg L-1 of alcoholic extract when applied concomitantly with the bacteria. This result was similarto bordeau mixture, indicating a control by direct antimicrobial activity. There was no systemic resistenceinduction for all treatments. The peroxidases induction was due to infectious pathogen process and notto the treatments with alcoholic extract. The results indicate the potential of M. glomerata alcoholicextract for the preventive control of cauliflower dark rot disease


Asunto(s)
Brassica , Producción de Cultivos , Mikania , Mikania , Plantas Medicinales , Producción de Alimentos , Xanthomonas campestris
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