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1.
Ecotoxicol Environ Saf ; 146: 68-75, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28571624

RESUMEN

Double-crested cormorants (Phalacrocorax auritus, DCCO) were orally exposed to Deepwater Horizon Mississippi Canyon 252 (DWH) oil to investigate oil-induced toxicological impacts. Livers were collected for multiple analyses including cytochrome P4501A (CYP1A) enzymatic activity and protein expression. CYP1A enzymatic activity was measured by alkoxyresorufin O-dealkylase (AROD) assays. Activities specific to the O-dealkylation of four resorufin ethers are reported: benzyloxyresorufin O-debenzylase (BROD), ethoxyresorufin O-deethylase (EROD), methoxyresorufin O-demethylase (MROD), and pentoxyresorufin O-depentylase (PROD). CYP1A protein expression was measured by western blot analysis with a CYP1A1 mouse monoclonal antibody. In study 1, hepatic BROD, EROD, and PROD activities were significantly induced in DCCO orally exposed to 20ml/kg body weight (bw) oil as a single dose or daily for 5 days. Western blot analysis revealed hepatic CYP1A protein induction in both treatment groups. In study 2 (5ml/kg bw oil or 10ml/kg bw oil, 21day exposure), all four hepatic ARODs were significantly induced. Western blots showed an increase in hepatic CYP1A expression in both treatment groups with a significant induction in birds exposed to 10ml/kg oil. Significant correlations were detected among all 4 AROD activities in both studies and between CYP1A protein expression and both MROD and PROD activities in study 2. EROD activity was highest for both treatment groups in both studies while BROD activity had the greatest fold-induction. While PROD activity values were consistently low, the fold-induction was high, usually 2nd highest to BROD activity. The observed induced AROD profiles detected in the present studies suggest both CYP1A4/1A5 DCCO isoforms are being induced after MC252 oil ingestion. A review of the literature on avian CYP1A AROD activity levels and protein expression after exposure to CYP1A inducers highlights the need for species-specific studies to accurately evaluate avian exposure to oil.

2.
Ecotoxicol Environ Saf ; 142: 79-86, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28390242

RESUMEN

Double-crested cormorants (Phalacrocorax auritus, DCCO) were orally exposed to Deepwater Horizon Mississippi Canyon 252 (DWH) oil to investigate oil-induced toxicological impacts. Livers were collected for multiple analyses including cytochrome P4501A (CYP1A) enzymatic activity and protein expression. CYP1A enzymatic activity was measured by alkoxyresorufin O-dealkylase (AROD) assays. Activities specific to the O-dealkylation of four resorufin ethers are reported: benzyloxyresorufin O-debenzylase (BROD), ethoxyresorufin O-deethylase (EROD), methoxyresorufin O-demethylase (MROD), and pentoxyresorufin O-depentylase (PROD). CYP1A protein expression was measured by western blot analysis with a CYP1A1 mouse monoclonal antibody. In study 1, hepatic BROD, EROD, and PROD activities were significantly induced in DCCO orally exposed to 20ml/kg body weight (bw) oil as a single dose or daily for 5 days. Western blot analysis revealed hepatic CYP1A protein induction in both treatment groups. In study 2 (5ml/kg bw oil or 10ml/kg bw oil, 21day exposure), all four hepatic ARODs were significantly induced. Western blots showed an increase in hepatic CYP1A expression in both treatment groups with a significant induction in birds exposed to 10ml/kg oil. Significant correlations were detected among all 4 AROD activities in both studies and between CYP1A protein expression and both MROD and PROD activities in study 2. EROD activity was highest for both treatment groups in both studies while BROD activity had the greatest fold-induction. While PROD activity values were consistently low, the fold-induction was high, usually 2nd highest to BROD activity. The observed induced AROD profiles detected in the present studies suggest both CYP1A4/1A5 DCCO isoforms are being induced after MC252 oil ingestion. A review of the literature on avian CYP1A AROD activity levels and protein expression after exposure to CYP1A inducers highlights the need for species-specific studies to accurately evaluate avian exposure to oil.

3.
Artículo en Inglés | MEDLINE | ID: mdl-39329319

RESUMEN

Vegetation communities in restored bottomland hardwood forests in northeast Indiana were studied 6-21 years after restoration to assess progress toward restoration objectives. The study focused on four sites that were restored to compensate for resource injuries after contaminant releases. The restored sites were compared with four reference-site conditions, including crops (prerestoration condition), old field communities representing a no-management alternative, locally sampled second-growth mature forests, and forest community types described by the US National Vegetation Classification (USNVC), which represent ideal or defining conditions of recognized vegetation communities. Fixed-area plots provided data on field-sampled environmental variables, vegetation, soil, and hydrological conditions for crops, old fields, restored areas, and mature forests. The USNVC database provided quantitative data for three historically and geographically relevant reference forest community types for comparison with the sampled communities. Results of nonmetric multidimensional scaling based on species cover revealed clear gradients relating to site age and canopy development. Along those gradients, restored areas demonstrated increasing similarity to mature forest reference communities in terms of floristic composition. Specifically, the floristic quality of restored areas was significantly greater than that of crops and old fields. Furthermore, soil health measurements of physical, chemical, and hydrological conditions indicated significant improvements in restored site soils compared with prerestoration conditions represented by cropland soils. Descriptions and data from the USNVC provided ecological context for restoration target conditions and facilitated the assessment of restoration recovery along a trajectory from starting conditions to those target conditions. Descriptions by USNVC also helped identify deviations from the intended restoration objectives (e.g., invasive species recruitment) and potential adaptive management actions to return sites to their intended trajectories. Integr Environ Assess Manag 2024;00:1-22. Published 2024. This article is a U.S. Government work and is in the public domain in the USA. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

4.
Artículo en Inglés | MEDLINE | ID: mdl-39291913

RESUMEN

Many sampling and analytical methods can estimate the abundance, distributions, and diversity of birds and other wildlife. However, challenges with sample size and analytical capacity can make these methods difficult to implement for resource-limited monitoring programs. To apprise efficient and attainable sampling designs for landbird monitoring programs with limited observational data, we used breeding season bird point survey data collected in 2016 at four forest restoration sites in Indiana, USA. We evaluated three subsets of observed species richness, total possibly breeding landbirds, Partners in Flight Regional Conservation Concern (PIF RCC) landbirds, and interior forest specialists (IFSs). Simulated surveys based on field data were used to conduct Bayesian Michaelis-Menten curve analyses estimating observed species as a function of sampling effort. On comparing simulated survey sets with multiple habitat types versus those with one habitat, we found that those with multiple habitat types had estimated 39%-83% greater observed PIF RCC species richness and required 41%-55% fewer visits per point to observe an equivalent proportion of PIF RCC species. Even with multiple habitats in a survey set, the number of visits per point required to detect 50% of observable species was 30% higher for PIF RCC species than for total breeding landbird species. Low detection rates of IFS species at two field sites made precise estimation of required effort to observe these species difficult. However, qualitatively, we found that only sites containing mature forest fragments had detections of several bird species designated as high-confidence IFS species. Our results suggest that deriving specialized species diversity metrics from point survey data can add value when interpreting those data. Additionally, designing studies to collect these metrics may require explicitly planning to visit multiple habitat types at a monitoring site and increasing the number of visits per survey point. Integr Environ Assess Manag 2024;00:1-15. © 2024 The Author(s). Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

5.
Artículo en Inglés | MEDLINE | ID: mdl-39347614

RESUMEN

The Natural Resource Damage Assessment and Restoration process assesses natural resource injury due to oil or chemical spills and calculates the damages to compensate the public for those injuries. Ecological restoration provides a means for recovering resources injured or lost due to contamination from oil or chemical spills by restoring the injured site after remediation, or acquiring or reconstructing equivalent resources off site to replace those lost due to the spill. In the case of restored forests, once restoration is implemented, monitoring of forest ecology helps keep recovery on track, with the maturation of forest vegetation, recovered soil conditions, and development of microbial, fungal, and faunal communities, necessary for ecologically functioning forests. This series of papers focuses on applying methods for monitoring restoration progress in forest vegetation and soils, and amphibian, avian, and mammalian communities, assessing strengths and weaknesses of different methods, and evaluating levels of effort needed to obtain accurate indications of forest ecological condition. Integr Environ Assess Manag 2024;00:1-5. © 2024 The Author(s). Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

6.
Arch Environ Contam Toxicol ; 61(4): 653-67, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21424223

RESUMEN

From September to November 2000, United States Fish and Wildlife Service biologists investigated incidents involving 221 bird deaths at 3 mine sites located in New Mexico and Arizona. These bird deaths primarily involved passerine and waterfowl species and were assumed to be linked to consumption of acid metalliferous water (AMW). Because all of the carcasses were found in or near pregnant leach solution ponds, tailings ponds, and associated lakes or storm water retention basins, an acute-toxicity study was undertaken using a synthetic AMW (SAMW) formulation based on the contaminant profile of a representative pond believed to be responsible for avian mortalities. An acute oral-toxicity trial was performed with a mixed-sex group of mallards (Anas platyrhynchos). After a 24-h pretreatment food and water fast, gorge drinking was evident in both SAMW treatment and control groups, with water consumption rates greatest during the initial drinking periods. Seven of nine treated mallards were killed in extremis within 12 h after the initiation of dose. Total lethal doses of SAMW ranged from 69.8 to 270.1 mL/kg (mean ± SE 127.9 ± 27.1). Lethal doses of SAMW were consumed in as few as 20 to 40 min after first exposure. Clinical signs of SAMW toxicity included increased serum uric acid, aspartate aminotransferase, creatine kinase, potassium, and P levels. PCV values of SAMW-treated birds were also increased compared with control mallards. Histopathological lesions were observed in the esophagus, proventriculus, ventriculus, and duodenum of SAMW-treated mallards, with the most distinctive being erosion and ulceration of the kaolin of the ventriculus, ventricular hemorrhage and/or congestion, and duodenal hemorrhage. Clinical, pathological, and tissue-residue results from this study are consistent with literature documenting acute metal toxicosis, especially copper (Cu), in avian species and provide useful diagnostic profiles for AMW toxicity or mortality events. Blood and kidney Cu concentrations were 23- and 6-fold greater, respectively, in SAMW mortalities compared with controls, whereas Cu concentrations in liver were not nearly as increased, suggesting that blood and kidney concentrations may be more useful than liver concentrations for diagnosing Cu toxicosis in wild birds. Based on these findings and other reports of AMW toxicity events in wild birds, we conclude that AMW bodies pose a significant hazard to wildlife that come in contact with them.


Asunto(s)
Patos , Metales Pesados/toxicidad , Metales Ligeros/toxicidad , Contaminantes Químicos del Agua/toxicidad , Administración Oral , Animales , Conducta Animal/efectos de los fármacos , Ingestión de Líquidos/efectos de los fármacos , Conducta de Ingestión de Líquido/efectos de los fármacos , Monitoreo del Ambiente/métodos , Femenino , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/patología , Concentración de Iones de Hidrógeno , Riñón/efectos de los fármacos , Riñón/patología , Longevidad/efectos de los fármacos , Masculino , Metales Pesados/química , Metales Ligeros/química , Ácido Nítrico/química , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/patología , Pruebas de Toxicidad Aguda
7.
Artículo en Inglés | MEDLINE | ID: mdl-32770800

RESUMEN

Efficient biodiversity surveys are critical for successful restoration monitoring and management. We studied the effect of varying sampling effort on the observed species richness of surveys of small mammals (trapping transects), bats (passive acoustic detection), and medium to large mammals (trail cameras). Field studies provided mammalian biodiversity data for 4 bottomland hardwood restoration sites in northeastern Indiana. Subsampled data were used to simulate monitoring surveys with a range of levels of effort. We then used hierarchical Bayesian nonlinear mixed models to analyze how different components of sampling effort affected observed species richness, a key monitoring outcome. We found that observed small mammal richness increased with the increased number of transects in a survey, while observed bat and medium to large mammal richness increased with the increased duration of sampling. Variation between sites was important for the observed richness of small mammals and bats but not for medium to large mammals. The key driver of richness observed in simulated surveys was related to the spatial scale at which target fauna interact with the habitat, with decreasing richness accompanied by a greater spatial scale of animal-habitat interactions. Our findings suggest taxon-specific recommendations for efficiently quantifying the mammalian diversity of managed sites. Integr Environ Assess Manag 2020;00:1-13. © 2020 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

8.
Ecol Appl ; 19(8): 2026-37, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20014576

RESUMEN

Locusts and grasshoppers cause considerable economic damage to agriculture worldwide. The Australian Plague Locust Commission uses multiple pesticides to control locusts in eastern Australia. Avian exposure to agricultural pesticides is of conservation concern, especially in the case of rare and threatened species. The aim of this study was to evaluate the probability of pesticide exposure of native avian species during operational locust control based on knowledge of species occurrence in areas and times of application. Using presence-absence data provided by the Birds Australia Atlas for 1998 to 2002, we developed a series of generalized linear models to predict avian occurrences on a monthly basis in 0.5 degrees grid cells for 280 species over 2 million km2 in eastern Australia. We constructed species-specific models relating occupancy patterns to survey date and location, rainfall, and derived habitat preference. Model complexity depended on the number of observations available. Model output was the probability of occurrence for each species at times and locations of past locust control operations within the 5-year study period. Given the high spatiotemporal variability of locust control events, the variability in predicted bird species presence was high, with 108 of the total 280 species being included at least once in the top 20 predicted species for individual space-time events. The models were evaluated using field surveys collected between 2000 and 2005, at sites with and without locust outbreaks. Model strength varied among species. Some species were under- or over-predicted as times and locations of interest typically did not correspond to those in the prediction data set and certain species were likely attracted to locusts as a food source. Field surveys demonstrated the utility of the spatially explicit species lists derived from the models but also identified the presence of a number of previously unanticipated species. These results also emphasize the need for special consideration of rare and threatened species that are poorly predicted by presence-absence models. This modeling exercise was a useful a priori approach in species risk assessments to identify species present at times and locations of locust control applications, and to discover gaps in our knowledge and need for further focused data collection.


Asunto(s)
Aves/fisiología , Saltamontes/fisiología , Control de Insectos/métodos , Agricultura/economía , Animales , Australia , Conservación de los Recursos Naturales , Demografía , Contaminantes Ambientales/efectos adversos , Modelos Biológicos , Plaguicidas/efectos adversos , Especificidad de la Especie , Factores de Tiempo
9.
Environ Toxicol Chem ; 28(3): 534-41, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18980388

RESUMEN

A century of mining and smelting activity at the Anaconda Smelter site in Anaconda, Montana, USA, has contaminated the surrounding soils and groundwater with metals. Soil microbial communities from six smelter-impacted sites and a nonimpacted site were compared to determine the long-term effects of a gradient of metal concentrations on microbial activity, biomass, functional diversity (Biolog microtiter plates), and structural diversity (denaturant gradient gel electrophoresis of 16S ribosomal DNA). Microbial activity and biomass were decreased in the smelter-impacted soils. Likewise, the functional and structural diversity of the microbial communities native to the smelter-impacted soils were shifted, relative to the microbial community, from the nonimpacted site. These shifts were significantly correlated with soil metal concentration and several soil physicochemical properties (pH, organic matter, NO(3), NH(4), etc.), which provides evidence of the importance of many environmental variables on microbial community dynamics in soils. Preliminary evidence of functional redundancy was observed within microbial communities native to the smelter-impacted sites, based on overlapping carbon substrate utilization patterns. However, due to culture-based selection bias, redundancy pertains only to a subset of the community and may not be ecologically relevant. Nevertheless, the effects of metal contamination on microbial communities in the present study are pronounced and results provide preliminary insight into the complex relationship between soil microbial community structure and function in anthropogenically disturbed soils.


Asunto(s)
Residuos Industriales/análisis , Metales/química , Metales/toxicidad , Microbiología del Suelo , Contaminantes del Suelo/química , Biomasa , Minería , Suelo/análisis
10.
Ecotoxicol Environ Saf ; 72(5): 1572-8, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19328550

RESUMEN

Sensitivities of a wildlife species, deer mice, to oxidants were evaluated. A single dose (1589 mg/kg body weight by intraperitoneal injection) of carbon tetrachloride, a typical hepatotoxicant, caused changes in GCL activity and GSH content in multiple organs of deer mice. Hepatic GCL activity and GSH content were depleted substantially (P<0.01), renal GCL activity increased (P<0.05). Blood, brain and heart GCL activities increased (P<0.05), whereas GSH contents decreased significantly. Deer mice were exposed to Pb, or Pb together with Cu and Zn via drinking water for 4 weeks. GCL activities were not significantly affected by treatments. GSH contents were increased significantly by Pb alone, Pb with medium and high concentrations of Cu and Zn. Effects of multi-metal-contaminated soil were investigated via lactational, juvenile and lifelong exposure to feed supplemented with soils. Metal-contaminated soils did not lead to significant effects in pups via lactation, 50-day exposure altered GSH content marginally, while 100-day exposure resulted in marked GCL activity depletion. After 100-day exposure, GCL activities of the medium soil-, high soil- and Pb-treated deer mice were only 53%, 40% and 46% of the control, respectively (P<0.0001).


Asunto(s)
Tetracloruro de Carbono/toxicidad , Glutamato-Cisteína Ligasa/metabolismo , Glutatión/metabolismo , Metales Pesados/toxicidad , Oxidantes/toxicidad , Estrés Oxidativo/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Envejecimiento , Animales , Encéfalo/efectos de los fármacos , Encéfalo/enzimología , Tetracloruro de Carbono/administración & dosificación , Cobre/toxicidad , Femenino , Glutamato-Cisteína Ligasa/sangre , Glutatión/sangre , Inyecciones Intraperitoneales , Riñón/efectos de los fármacos , Riñón/enzimología , Plomo/toxicidad , Hígado/efectos de los fármacos , Hígado/enzimología , Masculino , Miocardio/enzimología , Oxidantes/administración & dosificación , Peromyscus , Medición de Riesgo , Zinc/toxicidad
11.
Ecotoxicol Environ Saf ; 72(2): 572-8, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18403016

RESUMEN

Glutamate cysteine ligase (GCL), synthesizing gamma-glutamylcysteine from glutamate and cysteine, is the rate-limiting enzyme in glutathione (GSH) biosynthesis. GCL activity measurement was optimized in tissues from deer mice, Sprague Dawley rats, and mallard ducks. Varying glutamic acid concentrations from 5 to 80 mM did not affect GCL activities markedly, whereas cysteine concentrations from 2.5 to 40 mM influenced GCL activities substantially. Optimal cysteine concentrations for deer mouse, Sprague Dawley rat, and mallard duck (respectively) were 30, 30, and 20 mM in liver, 10, 10, and 20 mM in kidney, 20, 20, and 30 mM in brain, and 30 mM in heart for all three species. Responses of mallard duck GCL activity to acid metalliferous water were evaluated. After subacute exposure, low doses increased GCL activity and GSH content in liver by 48.3% and 54.4%, respectively. High doses reduced GCL activities significantly in liver and kidney to 31.2% and 43.0% of the control, respectively.


Asunto(s)
Animales Salvajes/metabolismo , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/toxicidad , Glutamato-Cisteína Ligasa/metabolismo , Metales/toxicidad , Animales , Relación Dosis-Respuesta a Droga , Patos , Contaminantes Ambientales/farmacocinética , Glutatión/biosíntesis , Metales/farmacocinética , Ratones , Ratas , Ratas Sprague-Dawley , Distribución Tisular
12.
Arch Environ Contam Toxicol ; 54(3): 516-24, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17955156

RESUMEN

Perchlorate (ClO (4)(-) ) is a thyroid hormone inhibitor and persistent environmental contaminant that has been shown to impair thyroid function and growth in ground-dwelling birds. In this study, we used the zebra finch (Taeniopygia guttata) as a model to examine the effects of environmentally relevant perchlorate concentrations on growth and behavior of a granivorous passerine. On post-hatch days (PHDs) 3-14, finch chicks were orally dosed once per day with either 0, 10, 100, or 1000 microg sodium perchlorate/g body mass, and multiple endpoints of growth and behavior were examined in birds up to 72 days of age. Mean (+/-SE) body mass and tibiotarsal length were significantly reduced in the 100 and 1000 microg/g dose groups from PHDs 3-14, and this reduction persisted until PHD 40. Mean liver mass (PHD 15) in the 100 and 1000 microg/g dose groups were significantly greater than controls. Mean brain mass and mean nuclear volume of the song control nucleus area X in brains of 72-day-old males did not differ among dose groups. All endpoints of finch behavior were significantly influenced by perchlorate exposure at the highest dose level. Compared to controls, birds in this dose group exhibited a greater begging intensity, decreased motivation for spontaneous movement (e.g., attempts to fly), and reduced capacity to wean themselves from parental care. On PHD 15, flight attempts were also significantly reduced in the 10 and 100 microg/g dose groups, and the proportion of perchlorate-dosed birds attempting flight was less than half that in the control group. This study demonstrates a dose-dependent alteration of multiple growth and behavioral endpoints in zebra finches exposed to environmentally relevant concentrations of perchlorate. Comparable exposures in the wild may also affect normal development and behavior in similarly sensitive avian granivores.


Asunto(s)
Contaminantes Ambientales/toxicidad , Pinzones/fisiología , Percloratos/toxicidad , Animales , Animales Recién Nacidos/fisiología , Conducta Animal/efectos de los fármacos , Encéfalo/efectos de los fármacos , Encéfalo/crecimiento & desarrollo , Relación Dosis-Respuesta a Droga , Conducta Exploratoria/efectos de los fármacos , Conducta Alimentaria/efectos de los fármacos , Femenino , Hígado/efectos de los fármacos , Hígado/crecimiento & desarrollo , Masculino , Tamaño de los Órganos/efectos de los fármacos
13.
N Engl J Med ; 346(9): 653-61, 2002 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-11870242

RESUMEN

BACKGROUND: Bisphosphonates are effective agents for the management of osteoporosis. Their low bioavailability and low potency necessitate frequent administration on an empty stomach, which may reduce compliance. Gastrointestinal intolerance limits maximal dosing. Although intermittent intravenous treatments have been used, the optimal doses and dosing interval have not been systematically explored. METHODS: We studied the effects of five regimens of zoledronic acid, the most potent bisphosphonate, on bone turnover and density in 351 postmenopausal women with low bone mineral density in a one-year, randomized, double-blind, placebo-controlled trial. Women received placebo or intravenous zoledronic acid in doses of 0.25 mg, 0.5 mg, or 1 mg at three-month intervals. In addition, one group received a total annual dose of 4 mg as a single dose, and another received two doses of 2 mg each, six months apart. Lumbar-spine bone mineral density was the primary end point. RESULTS: There were similar increases in bone mineral density in all the zoledronic acid groups to values for the spine that were 4.3 to 5.1 percent higher than those in the placebo group (P<0.001) and values for the femoral neck that were 3.1 to 3.5 percent higher than those in the placebo group (P<0.001). Biochemical markers of bone resorption were significantly suppressed throughout the study in all zoledronic acid groups. Myalgia and pyrexia occurred more commonly in the zoledronic acid groups, but treatment-related dropout rates were similar to that in the placebo group. CONCLUSIONS: Zoledronic acid infusions given at intervals of up to one year produce effects on bone turnover and bone density as great as those achieved with daily oral dosing with bisphosphonates with proven efficacy against fractures, suggesting that an annual infusion of zoledronic acid might be an effective treatment for postmenopausal osteoporosis.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Remodelación Ósea/efectos de los fármacos , Difosfonatos/administración & dosificación , Imidazoles/administración & dosificación , Osteoporosis Posmenopáusica/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Colágeno/sangre , Colágeno/orina , Colágeno Tipo I , Creatinina/orina , Difosfonatos/efectos adversos , Difosfonatos/farmacología , Método Doble Ciego , Esquema de Medicación , Femenino , Fracturas Óseas/prevención & control , Humanos , Imidazoles/efectos adversos , Imidazoles/farmacología , Infusiones Intravenosas , Persona de Mediana Edad , Osteoporosis Posmenopáusica/fisiopatología , Péptidos/sangre , Péptidos/orina , Ácido Zoledrónico
15.
Environ Toxicol Chem ; 25(11): 2964-70, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17089720

RESUMEN

Huge aggregations of flightless locust nymphs pose a serious threat to agriculture when they reach plague proportions but provide a very visible and nutritious resource for native birds. Locust outbreaks occur in spring and summer months in semiarid regions of Australia. Fenitrothion, an organophosphate pesticide, is sprayed aerially to control locust plagues. To evaluate fenitrothion exposure in birds attending locust outbreaks, we measured total plasma cholinesterase (ChE), butrylcholinesterase (BChE), and acetylcholinesterase (AChE) activities in four avian species captured pre- and postfenitrothion application and ChE reactivation in birds caught postspray only. Eleven of 21 plasma samples from four species had ChE activity below the diagnostic threshold (two standard deviations below the mean ChE activity of prespray samples). Granivorous zebra finches (Taeniopygia guttata) and insectivorous white-winged trillers (Lalage sueurii) had significantly lower mean plasma total ChE, BChE, and AChE activity postspray, while other insectivores, white-browed (Artamus superciliosus) and masked woodswallows (Artamus personatus), did not. Cholinesterase was reactivated in 19 of the 73 plasma samples and in one of three brain samples. We conclude that native bird species are exposed to fenitrothion during locust control operations. This exposure could have detrimental impacts, as both locust outbreaks and avian reproductive events are stimulated by heavy summer rainfall, leading to co-occurrence of locust control and avian breeding activities.


Asunto(s)
Inhibidores de la Colinesterasa/toxicidad , Fenitrotión/toxicidad , Insecticidas/toxicidad , Passeriformes/metabolismo , Acetilcolinesterasa/sangre , Animales , Encéfalo/enzimología , Butirilcolinesterasa/sangre , Colinesterasas/análisis , Colinesterasas/sangre , Saltamontes , Control de Insectos , Queensland
16.
Environ Toxicol Chem ; 25(2): 458-69, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16519307

RESUMEN

We live-trapped 40 northern pocket gophers across two years from the Anaconda Smelter Superfund Site, Anaconda, Montana, USA, to determine their exposure to five metal contaminants and effects of exposure on selected measurements. Soil, gopher blood, liver, kidney, and carcass samples were analyzed for arsenic, cadmium, lead, copper, and zinc. Hematological parameters, kidney and liver porphyrins, and red blood cell delta-aminolevulinic acid dehydratase (ALAD) activity were also measured. Micronutrients Cu and Zn were detected in all tissues analyzed, and Cd, Pb, and As were detected less frequently. We report differences in metal distribution among different tissues and differences in bioaccumulation for different metals within the same tissue. No significant differences were observed in concentrations of Zn or Cu in any tissue across the study site, but relationships between lead in soil and lead in carcass proved especially strong (r2 = 0.80; p < 0.001; n = 18). Among biomarker data, we observed a negative relationship between concentration of lead in the soil and ALAD activity in gophers with detectable concentrations of lead in their blood (r2 = 0.45; p = 0.006; n = 15). Results of this study suggest that northern pocket gophers are useful biomonitors of environmental Pb, Cd, and As contamination, and their broad geographic range across North America could allow them to be an important component of site-specific metals assessments.


Asunto(s)
Arsénico/farmacocinética , Ardillas Terrestres , Residuos Peligrosos , Metales Pesados/farmacocinética , Contaminantes del Suelo/farmacocinética , Animales , Arsénico/análisis , Biomarcadores/análisis , Recuento de Células Sanguíneas/veterinaria , Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Dinámica Poblacional , Porfobilinógeno Sintasa/sangre , Contaminantes del Suelo/análisis , Distribución Tisular
17.
Environ Toxicol Chem ; 25(6): 1574-84, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16764476

RESUMEN

We collected adult cave swallows (Petrochelidon fulva) and cliff swallows (P. pyrrhonota) during the breeding seasons in 1999 and 2000 from eight locations along the Rio Grande from Brownsville to El Paso (unless otherwise specified, all locations are Texas, USA) and an out-of-basin reference location. Body mass, spleen mass, hepatosomatic index (HSI), gonadosomatic index (GSI), thyroxine (T4) in plasma, DNA damage measured as the half-peak coefficient of variation of DNA content (HPCV) in blood cells, as well as acetylcholinesterase and butyrylcholinesterase in brain were compared with concentrations of organochlorines, metals, and metalloids in carcasses to determine potential effects of contaminants on swallows during the breeding season. Concentrations of 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p'-DDE) were significantly greater in swallows from El Paso than in those from most locations, except for Pharr and Llano Grande. All swallows from these three locations had p,p'-DDE concentrations of 3 microg/g wet weight or greater. Swallows from El Paso either had or shared the highest concentrations of p,p'-DDE, polychlorinated biphenyls, and 13 inorganic elements. Swallows from El Paso exhibited greater spleen mass and HPCV values as well as lower T4 values compared with those from other locations. Thyroxine was a potential biomarker of contaminant exposure in swallows of the Rio Grande, because it was negatively correlated with p,p'-DDE and Se. Spleen mass was positively correlated with selenium and HSI and negatively correlated with body mass, GSI, Mn, and Ni. Overall, the present study suggests that insectivorous birds living in areas of high agricultural and industrial activity along the Rio Grande bioaccumulate environmental contaminants. These contaminants, particularly p,p'-DDE, may be among multiple factors that impact endocrine and hematopoietic function in Rio Grande swallows.


Asunto(s)
Exposición a Riesgos Ambientales , Monitoreo del Ambiente , Contaminantes Ambientales/análisis , Animales , Peso Corporal/efectos de los fármacos , Citometría de Flujo , Tamaño de los Órganos/efectos de los fármacos , Radioinmunoensayo , Golondrinas , Texas , Tiroxina/sangre
18.
Integr Environ Assess Manag ; 12(2): 284-95, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26465231

RESUMEN

Ecological restorations of contaminated sites balance the human and ecological risks of residual contamination with the benefits of ecological recovery and the return of lost ecological function and ecosystem services. Risk and recovery are interrelated dynamic conditions, changing as remediation and restoration activities progress through implementation into long-term management and ecosystem maturation. Monitoring restoration progress provides data critical to minimizing residual contaminant risk and uncertainty, while measuring ecological advancement toward recovery goals. Effective monitoring plans are designed concurrently with restoration plan development and implementation and are focused on assessing the effectiveness of activities performed in support of restoration goals for the site. Physical, chemical, and biotic measures characterize progress toward desired structural and functional ecosystem components of the goals. Structural metrics, linked to ecosystem functions and services, inform restoration practitioners of work plan modifications or more substantial adaptive management actions necessary to maintain desired recovery. Monitoring frequency, duration, and scale depend on specific attributes and goals of the restoration project. Often tied to restoration milestones, critical assessment of monitoring metrics ensures attainment of risk minimization and ecosystem recovery. Finally, interpretation and communication of monitoring findings inform and engage regulators, other stakeholders, the scientific community, and the public. Because restoration activities will likely cease before full ecosystem recovery, monitoring endpoints should demonstrate risk reduction and a successional trajectory toward the condition established in the restoration goals. A detailed assessment of the completed project's achievements, as well as unrealized objectives, attained through project monitoring, will determine if contaminant risk has been minimized, if injured resources have recovered, and if ecosystem services have been returned. Such retrospective analysis will allow better planning for future restoration goals and strengthen the evidence base for quantifying injuries and damages at other sites in the future.


Asunto(s)
Monitoreo del Ambiente/métodos , Restauración y Remediación Ambiental/métodos , Conservación de los Recursos Naturales , Ecosistema , Medición de Riesgo
19.
J Bone Miner Res ; 20(2): 227-31, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15647816

RESUMEN

UNLABELLED: Mutations in the UBA domain of SQSTM1 are a common cause of Paget's disease of bone. Here we show that the most common disease-causing mutation (P392L) is carried on a shared haplotype, consistent with a founder effect and a common ancestral origin. INTRODUCTION: Paget's disease of bone (PDB) is a common condition with a strong genetic component. Mutations affecting the ubiquitin-associated (UBA) domain of sequestosome 1 (SQSTM1) have recently been shown to be an important cause of PDB. The most common mutation results in a proline to leucine amino acid change at codon 392 (P392L), and evidence has been presented to suggest that there may be a recurrent mutation rather than a founder mutation on an ancestral chromosome. Because marked geographical differences exist in the prevalence of PDB, we have investigated the frequency of SQSTM1 mutations in different populations and looked for a founder effect on chromosomes bearing SQSTM1 UBA domain mutations. MATERIALS AND METHODS: We conducted mutation screening of SQSTM1 and performed haplotype analysis using the PHASE software program in 83 kindreds with familial PDB, recruited mainly through clinic referrals in the United Kingdom, Australia, and New Zealand. Similar studies were conducted in 311 individuals with PDB who did not have a family history and 375 age- and sex-matched controls from the United Kingdom. RESULTS: The proportion of patients with familial PDB who had SQSTM1 UBA domain mutations varied somewhat between referral centers from 7.1% (Sydney, Australia) to 50% (Perth, Australia), but the difference between centers was not statistically significant. Haplotype analysis in 311 British patients with PDB who did not have a family history and 375 age- and sex-matched British controls showed that two common haplotypes accounted for about 90% of alleles at the SQSTM1 locus, as defined by common single nucleotide polymorphisms (SNPs) in exon 6 (C916T, G976A) and the 3'UTR (C2503T, T2687G). These were H1 (916T-976A-2503C-2687T) and H2 (916C-976G-2503T-2687G). There was no significant difference in haplotype distribution in PDB cases and controls, but the P392L mutation was found on the H2 haplotype in 25/27 cases (93%), which is significantly more often than expected given the allele frequencies in the normal population (odds ratio, 13.2; 95% CI, 3.1-56.4; p < 0.0001). Similar findings were observed in familial PDB, where 12/13 (92%) of P392L mutations were carried on H2 (odds ratio 17.2; 95% CI, 2.2-138; p = 0.001). CONCLUSIONS: These results provide strong evidence for a founder effect of the SQSTM1 P392L mutation in PDB patients of British descent, irrespective of family history. Our results imply that these individuals share a common ancestor and that the true rate of de novo mutations may be lower than previously suspected.


Asunto(s)
Osteítis Deformante/etnología , Osteítis Deformante/genética , Osteítis Deformante/metabolismo , Proteínas/genética , Ubiquitina/química , Regiones no Traducidas 3' , Proteínas Adaptadoras Transductoras de Señales , Alelos , Cartilla de ADN/química , Exones , Femenino , Efecto Fundador , Genotipo , Haplotipos , Humanos , Intrones , Masculino , Modelos Genéticos , Mutación , Oportunidad Relativa , Polimorfismo Genético , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas , Estructura Terciaria de Proteína , Proteína Sequestosoma-1 , Programas Informáticos , Reino Unido
20.
Integr Environ Assess Manag ; 11(3): 355-69, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25556986

RESUMEN

The North Atlantic Landscape Conservation Cooperative LCC (NA LCC) is a public-private partnership that provides information to support conservation decisions that may be affected by global climate change (GCC) and other threats. The NA LCC region extends from southeast Virginia to the Canadian Maritime Provinces. Within this region, the US National Climate Assessment documented increases in air temperature, total precipitation, frequency of heavy precipitation events, and rising sea level, and predicted more drastic changes. Here, we synthesize literature on the effects of GCC interacting with selected contaminant, nutrient, and environmental processes to adversely affect natural resources within this region. Using a case study approach, we focused on 3 stressors with sufficient NA LCC region-specific information for an informed discussion. We describe GCC interactions with a contaminant (Hg) and 2 complex environmental phenomena-freshwater acidification and eutrophication. We also prepared taxa case studies on GCC- and GCC-contaminant/nutrient/process effects on amphibians and freshwater mussels. Several avian species of high conservation concern have blood Hg concentrations that have been associated with reduced nesting success. Freshwater acidification has adversely affected terrestrial and aquatic ecosystems in the Adirondacks and other areas of the region that are slowly recovering due to decreased emissions of N and sulfur oxides. Eutrophication in many estuaries within the region is projected to increase from greater storm runoff and less denitrification in riparian wetlands. Estuarine hypoxia may be exacerbated by increased stratification. Elevated water temperature favors algal species that produce harmful algal blooms (HABs). In several of the region's estuaries, HABs have been associated with bird die-offs. In the NA LCC region, amphibian populations appear to be declining. Some species may be adversely affected by GCC through higher temperatures and more frequent droughts. GCC may affect freshwater mussel populations via altered stream temperatures and increased sediment loading during heavy storms. Freshwater mussels are sensitive to un-ionized ammonia that more toxic at higher temperatures. We recommend studying the interactive effects of GCC on generation and bioavailability of methylmercury and how GCC-driven shifts in bird species distributions will affect avian exposure to methylmercury. Research is needed on how decreases in acid deposition concurrent with GCC will alter the structure and function of sensitive watersheds and surface waters. Studies are needed to determine how GCC will affect HABs and avian disease, and how more severe and extensive hypoxia will affect fish and shellfish populations. Regarding amphibians, we suggest research on 1) thermal tolerance and moisture requirements of species of concern, 2) effects of multiple stressors (temperature, desiccation, contaminants, nutrients), and 3) approaches to mitigate impacts of increased temperature and seasonal drought. We recommend studies to assess which mussel species and populations are vulnerable and which are resilient to rising stream temperatures, hydrological shifts, and ionic pollutants, all of which are influenced by GCC.


Asunto(s)
Cambio Climático , Conservación de los Recursos Naturales , Contaminación del Agua/estadística & datos numéricos , Animales , Organismos Acuáticos/clasificación , Organismos Acuáticos/crecimiento & desarrollo , Océano Atlántico , Biodiversidad , Ecosistema , Monitoreo del Ambiente , Eutrofización , Agua Dulce/química , Mercurio/análisis
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