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1.
Sci Total Environ ; 658: 558-569, 2019 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-30580211

RESUMEN

Understanding lead (Pb) and antimony (Sb) speciation associated with the weathering of bullets at shooting ranges is essential for identifying species migration potential to local watersheds and for assessing the overall toxicity of shooting range soils. In the present study, we fired 2000 5.56 mm bullets into newly constructed and instrumented target berms composed of well-characterized test soils (sand, sandy loam, loamy sand, silt loam) and collected berm pore water runoff and soil samples over five summers (2011 to 2015). We tracked the chemical transformations of Pb and Sb released during bullet weathering as a function of time and soil properties. During 2014 summer, an amendment of ferrous chloride (FeCl2) with a calcium carbonate (CaCO3) buffer was added to a subset of the berms of each soil type to test this remediation strategy. Bulk speciation analysis coupled with micro-scale spectroscopic methods show that both Sb(III) and Sb(V) species are present in soil solution depending on the soil matrix type, but Sb(III) was not observed after 9 months of weathering. In general, Sb was found to be more mobile than Pb, attributable to the relatively low solubility of the dominant Pb phases present in the crust forming around bullet fragments and within soil. The oxidation of Pb(0) resulted in a mixture of lead oxide, lead carbonate, and lead sorbed onto iron(III) oxides. We found a higher degree of metal(loid) mobilization (higher dissolved metal concentrations) in the berms made from the sandy soils. In contrast, silt loam soil was found to be more effective at immobilizing metal(loid)s. Furthermore, we observed that an iron-oxide type amendment may be effective at further reducing Pb and Sb runoff. Results from this study provide insight into the fate and transport of metal(loid)s within small arms target ranges and address a potential method for metal(loid) immobilization.

2.
Bull Environ Contam Toxicol ; 100(5): 603-608, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29532132

RESUMEN

Military ranges are unlike many waste sites because the contaminants, both energetics and metals, are heterogeneously distributed in soil during explosive detonation or ballistic impact and cannot be readily characterized using conventional grab sampling. The Incremental Sampling Methodology (ISM) has been successful for characterization of energetic contamination in soils, but no published ISM processing studies for soils with small arms range metals such as Pb, Cu, Sb, and Zn exists. This study evaluated several ISM sample-processing steps: (1) field splitting to reduce the sample mass shipped to the analytical laboratory, (2) necessity of milling, and (3) processing a larger subsample mass for digestion in lieu of milling. Cone-and-quartering and rotary sectorial splitting techniques yielded poor precision and positively skewed distributions. Hence, an increase in digestion mass from 2 to 10 g was evaluated with milled and unmilled samples. Unmilled samples yielded results with the largest variability regardless of aliquot mass.


Asunto(s)
Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Personal Militar , Suelo/química , Armas
3.
Bull Environ Contam Toxicol ; 100(1): 147-154, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29299633

RESUMEN

Research shows grab sampling is inadequate for evaluating military ranges contaminated with energetics because of their highly heterogeneous distribution. Similar studies assessing the heterogeneous distribution of metals at small-arms ranges (SAR) are lacking. To address this we evaluated whether grab sampling provides appropriate data for performing risk analysis at metal-contaminated SARs characterized with 30-48 grab samples. We evaluated the extractable metal content of Cu, Pb, Sb, and Zn of the field data using a Monte Carlo random resampling with replacement (bootstrapping) simulation approach. Results indicate the 95% confidence interval of the mean for Pb (432 mg/kg) at one site was 200-700 mg/kg with a data range of 5-4500 mg/kg. Considering the U.S. Environmental Protection Agency screening level for lead is 400 mg/kg, the necessity of cleanup at this site is unclear. Resampling based on populations of 7 and 15 samples, a sample size more realistic for the area yielded high false negative rates.


Asunto(s)
Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Armas , Restauración y Remediación Ambiental , Suelo
4.
Bull Environ Contam Toxicol ; 100(1): 155-161, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29270645

RESUMEN

This study compares conventional grab sampling to incremental sampling methodology (ISM) to characterize metal contamination at a military small-arms-range. Grab sample results had large variances, positively skewed non-normal distributions, extreme outliers, and poor agreement between duplicate samples even when samples were co-located within tens of centimeters of each other. The extreme outliers strongly influenced the grab sample means for the primary contaminants lead (Pb) and antinomy (Sb). In contrast, median and mean metal concentrations were similar for the ISM samples. ISM significantly reduced measurement uncertainty of estimates of the mean, increasing data quality (e.g., for environmental risk assessments) with fewer samples (e.g., decreasing total project costs). Based on Monte Carlo resampling simulations, grab sampling resulted in highly variable means and upper confidence limits of the mean relative to ISM.


Asunto(s)
Monitoreo del Ambiente/métodos , Metales/análisis , Contaminantes del Suelo/análisis , Suelo/química , Medición de Riesgo
5.
Eur Respir J ; 33(2): 305-11, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19010992

RESUMEN

When do infants and young children with cystic fibrosis acquire infection with Pseudomonas aeruginosa? Can this be eradicated when first detected? Children <6 yrs of age participated in an annual bronchoalveolar lavage (BAL)-based microbiological surveillance programme in Perth, Australia. When P. aeruginosa was detected, an eradication programme using combination treatment with i.v., oral and nebulised antibiotics was undertaken. Repeat BAL was performed 3 months following treatment, to assess eradication success. P. aeruginosa was detected in 33 (28.4%) children; median (range) age at detection was 30.5 (3.3-71.4) months. P. aeruginosa was mucoid at detection in six (18.2%) out of 33 patients and associated with respiratory symptoms in 16 (48.5%) out of 33 children. In total, 26 children underwent eradication therapy, with P. aeruginosa eradicated in 20 (77%) out of 26 following one eradication cycle and in three (total 88%) additional children following a second cycle. Eradication was associated with a significant decrease in neutrophil elastase and interleukin-1beta in BAL fluid 12 months post eradication. Eradication of Pseudomonas aeruginosa infection is achievable in young children with cystic fibrosis for up to 5 yrs using combination i.v., oral and nebulised antibiotic therapy and is associated with reduced pulmonary inflammation 12 months post eradication.


Asunto(s)
Fibrosis Quística/complicaciones , Fibrosis Quística/tratamiento farmacológico , Infecciones por Pseudomonas/complicaciones , Infecciones por Pseudomonas/tratamiento farmacológico , Administración Oral , Líquido del Lavado Bronquioalveolar , Preescolar , Fibrosis Quística/epidemiología , Femenino , Humanos , Lactante , Inflamación , Interleucina-1beta/metabolismo , Elastasa de Leucocito/metabolismo , Pulmón/microbiología , Pulmón/patología , Masculino , Infecciones por Pseudomonas/epidemiología , Pseudomonas aeruginosa/metabolismo , Factores de Tiempo
6.
Allergy ; 62(4): 401-7, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17362251

RESUMEN

BACKGROUND: The relationship between atopy and bronchial allergy in young children is not completely understood. OBJECTIVE: To examine the association between response to bronchial allergen challenge, immune markers of atopy and other clinical characteristics in 5- to 6-year-old children. METHODS: Children with positive skin test (SPT) to aeroallergen, together with a proportion of SPT negative children (as controls), were recruited from a birth cohort of 198 children at high risk of developing atopic disease and underwent allergen challenge. RESULTS: Thirty-seven children (26 atopic and 11 SPT negative), median age 74.5 months, were challenged: 31 with house dust mite and six with grass allergen. Only atopic children responded to challenge: n = 12/26 (46%). Wheal size [odds ratio (OR) 2.5 (1.2-5.3), P = 0.01], allergen-specific immunoglobulin E (IgE) [OR 3.4 (1.23-9.61), P = 0.02], total IgE [OR 8.6 (1.1-68.7), P = 0.04], current wheeze [OR 12 (1.7-81.7), P = 0.006] and persistent eczema [OR 11.0 (1.7-68.3), P = 0.006] emerged as the strongest independent predictors of response to allergen challenge. Prediction of response to allergen challenge was significantly improved when immune markers of atopy, and in particular wheal size, were combined with clinical characteristics. CONCLUSION: The relationship between atopy and bronchial allergy is quantitative at this age. There may be potential to create more powerful indicators of the presence of respiratory allergy in young children when immunological markers of atopy are considered quantitatively and when combined with clinical history of coexistent allergic disease.


Asunto(s)
Alérgenos/administración & dosificación , Hipersensibilidad Inmediata/inmunología , Alérgenos/inmunología , Pruebas de Provocación Bronquial , Niño , Preescolar , Femenino , Humanos , Hipersensibilidad Inmediata/sangre , Hipersensibilidad Inmediata/epidemiología , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Masculino , Pruebas Cutáneas
7.
Environ Sci Technol ; 40(24): 7521-7, 2006 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-17256489

RESUMEN

The detailed physical characteristics of the subarctic snowpack must be known to quantify the exchange of adsorbed pollutants between the atmosphere and the snow cover. For the first time, the combined evolutions of specific surface area (SSA), snow stratigraphy, temperature, and density were monitored throughout winter in central Alaska. We define the snow area index (SAI) as the vertically integrated surface area of snow crystals, and this variable is used to quantify pollutants' adsorption. Intense metamorphism generated by strong temperature gradients formed a thick depth hoar layer with low SSA (90 cm(2) g-1) and density (200 kg m(-3)), resulting in a low SAI. After snowpack buildup in autumn, the winter SAI remained around 1000 m(2)/m(2) of ground, much lower than the SAI of the Arctic snowpack, 2500 m(2) m-(2). With the example of PCBs 28 and 180, we calculate that the subarctic snowpack is a smaller reservoir of adsorbed pollutants than the Arctic snowpack and less efficiently transfers adsorbed pollutants from the atmosphere to ecosystems. The difference is greater for the more volatile PCB 28. With climate change, snowpack structure will be modified, and the snowpack's ability to transfer adsorbed pollutants from the atmosphere to ecosystems may be reduced, especially for the more volatile pollutants.


Asunto(s)
Contaminantes Atmosféricos , Nieve , Adsorción , Alaska
8.
J Paediatr Child Health ; 37(5): 441-5, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11885706

RESUMEN

OBJECTIVES: To assess awareness of sudden infant death syndrome (SIDS) and risk reducing recommendations in a sample of mothers in North Queensland, Australia, and to examine their infant care practices. METHOD: Interviews conducted with 195 women using a standardized questionnaire between October 1997 and January 1998. RESULTS: 191 questionnaires analyzed; 134 (70.2%) Caucasian and 57 (29.8%) indigenous women. Four women with previous SIDS experience were excluded from the analysis. Eight (4.2%) had never heard of SIDS. Twenty-nine (15.2%) had heard of SIDS and 154 (80.6%) had heard of SIDS and could list risk recommendations to reduce its incidence. Multivariate analysis identified ethnicity as the only significant predictor of maternal knowledge. Indigenous mothers knew less about SIDS: adjusted odds ratio (OR) = 5.4; 95% confidence interval (CI) = [2.1-14.0]. Avoidance of prone sleeping was the most frequently identified recommendation (n = 132), with no smoking in pregnancy (n = 48) and breastfeeding (n = 40) identified least frequently. There were 80.2% of mothers who put their infant in non-prone positions to sleep. Only 48 (25%) women identified smoking in pregnancy, and 93 (48.6%) smoking in the infant's environment as risk factors. Indigenous women were more likely to smoke in their pregnancy (P = 0.004), bed share with their infant (P = 0.0001), and have smokers in the home. CONCLUSION: There is a high level of awareness of SIDS and the main associated risk factor of infant prone sleeping, but the link between SIDS and smoking requires further emphasis. Future campaigns should ensure the SIDS message is delivered more effectively to the indigenous communities.


Asunto(s)
Conductas Relacionadas con la Salud , Conocimientos, Actitudes y Práctica en Salud , Cuidado del Lactante/métodos , Madres/estadística & datos numéricos , Muerte Súbita del Lactante/epidemiología , Muerte Súbita del Lactante/prevención & control , Adulto , Concienciación , Femenino , Conductas Relacionadas con la Salud/etnología , Humanos , Lactante , Cuidado del Lactante/normas , Recién Nacido , Oportunidad Relativa , Embarazo , Queensland/epidemiología , Factores de Riesgo , Muerte Súbita del Lactante/etnología
9.
Res Vet Sci ; 47(2): 203-7, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2477881

RESUMEN

The concentrations of bovine acute phase proteins were monitored in plasma following experimental infection with Pasteurella haemolytica and Ostertagia ostertagi and after endotoxin administration. Raised levels of haptoglobin, alpha 1 proteinase inhibitor and seromucoid were detected after pasteurella infection and endotoxin administration. Ceruloplasmin levels increased after endotoxin administration but not during pasteurella infection. Raised levels of the four acute phase proteins were found in eight of 19 calves infected with ostertagia but showed a variable pattern and did not correlate with plasma pepsinogen increases. Bovine alpha 1 antichymotrypsin and alpha 2 macroglobulin were identified as acute phase reactants.


Asunto(s)
Reacción de Fase Aguda/veterinaria , Enfermedades de los Bovinos/etiología , Inflamación/veterinaria , Ostertagiasis/veterinaria , Infecciones por Pasteurella/veterinaria , Choque Séptico/veterinaria , Tricostrongiloidiasis/veterinaria , Proteínas de Fase Aguda/análisis , Reacción de Fase Aguda/etiología , Animales , Bovinos , Ceruloplasmina/análisis , Endotoxinas , Escherichia coli , Femenino , Haptoglobinas/análisis , Lipopolisacáridos , Masculino , Orosomucoide/análisis , Ostertagiasis/complicaciones , Infecciones por Pasteurella/complicaciones , Inhibidores de Proteasas/análisis , Choque Séptico/complicaciones , alfa 1-Antiquimotripsina/sangre , alfa-Macroglobulinas/análisis
10.
J Reprod Fertil Suppl ; 39: 293-8, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2621731

RESUMEN

Behaviour, vaginal cytology and plasma progesterone concentrations were monitored during oestrus in a group of 6 beagle bitches before intrauterine insemination with frozen semen. At intervals after insemination, the reproductive tracts were examined for evidence of conception, which occurred in 5 of the bitches. One pregnant bitch had received treatment with stilboestrol before insemination.


Asunto(s)
Perros/fisiología , Inseminación Artificial/veterinaria , Animales , Femenino , Masculino , Progesterona/sangre , Preservación de Semen , Conducta Sexual Animal , Motilidad Espermática , Vagina/citología
11.
Res Vet Sci ; 45(1): 107-10, 1988 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2464844

RESUMEN

The levels of five acute phase reactants and serum glycoproteins were measured in dogs following surgical trauma. Canine C-reactive protein peaked 24 hours after surgery and peak levels of ceruloplasmin, haptoglobin and seromucoid were detected on the fourth to sixth days. Levels of serum glycoproteins varied in a similar manner to ceruloplasmin, haptoglobin and seromucoid. There was very little variation in the levels of alpha 1 antitrypsin.


Asunto(s)
Proteínas de Fase Aguda/sangre , Perros/cirugía , Glicoproteínas/sangre , Reacción de Fase Aguda/veterinaria , Animales , Aorta Abdominal/cirugía , Femenino , Masculino , Periodo Posoperatorio
12.
Res Vet Sci ; 44(3): 391-3, 1988 May.
Artículo en Inglés | MEDLINE | ID: mdl-2457244

RESUMEN

Canine serum alpha 1-proteinase inhibitor is not a major acute phase reactant in the dog, unlike the equivalent protein in humans. The possibility that an alternative protease inhibitor system is stimulated during the acute phase response in the dog was investigated. alpha 2-macroglobulin was not an acute phase reactant, but an inhibitor of elastase was identified in canine serum which could be separated from proteinase inhibitor by gel filtration and which was shown to be an acute phase reactant. This protein has been named canine elastase inhibitor.


Asunto(s)
Proteínas de Fase Aguda/sangre , Proteínas Sanguíneas , Perros/sangre , Elastasa Pancreática/antagonistas & inhibidores , Animales , alfa 1-Antitripsina
14.
Res Vet Sci ; 44(1): 82-8, 1988 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2453907

RESUMEN

The serum levels of five proteins, alpha 1 antitrypsin, ceruloplasmin, fibrinogen, haptoglobin and seromucoid, were measured daily in calves after the subcutaneous injection of oil of turpentine. Raised concentrations were detected on the second and third days after injection with peak levels occurring on the fourth to seventh days and returning to normal by the 17th day. Levels of four of these proteins, alpha 1 antitrypsin, ceruloplasmin, haptoglobin and seromucoid were compared in the same calves following three different doses of turpentine. Levels of haptoglobin and seromucoid varied with the dose whereas ceruloplasmin and alpha 1 antitrypsin levels did not.


Asunto(s)
Proteínas de Fase Aguda/sangre , Reacción de Fase Aguda/veterinaria , Bovinos/sangre , Inflamación/veterinaria , Trementina/farmacología , Proteínas de Fase Aguda/análisis , Reacción de Fase Aguda/inducido químicamente , Animales , Inyecciones Subcutáneas , Trementina/administración & dosificación
15.
Equine Vet J ; 19(2): 138-42, 1987 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3569196

RESUMEN

Six mares were studied over a period of two years under varying conditions of lighting from total darkness to normal ambient lighting. The mares continued to cycle during the winter under natural lighting and also when kept in total darkness. Circulating melatonin, progesterone and oestrogen concentrations were determined and related to clinical changes in the reproductive tract.


Asunto(s)
Estro/fisiología , Caballos/fisiología , Luz , Preñez/fisiología , Conducta Sexual Animal/fisiología , Anestro/fisiología , Animales , Femenino , Melatonina/sangre , Embarazo , Progesterona/sangre
16.
J Reprod Fertil Suppl ; 35: 269-76, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3479582

RESUMEN

Plasma prolactin concentrations were measured in mares using an homologous radioimmunoassay. An annual rhythm in plasma prolactin was found, with concentrations higher during the summer than during the winter. In addition to this seasonal pattern, occasional high concentrations of prolactin were seen when concentrations were otherwise basal. Blood samples taken from mares during an oestrous cycle in October-November showed that prolactin values were basal for most of the cycle, with a marked rise in prolactin shortly before the onset of oestrus. This prolactin peak was associated with an increase in the size of the largest follicle, and with a peak of PGFM in some mares, but did not appear to be related to the LH surge. In oestrous cycles in March and May-June, there was a wide variation in the baseline of prolactin secretion, in accordance with the seasonal pattern already mentioned. However, the peak of prolactin seen around oestrus in October-November was less obvious in March and May-June. Post-partum mares showed a high but irregular profile of prolactin concentrations with no clear-cut pattern in relation to the oestrous cycle.


Asunto(s)
Estro/sangre , Caballos/sangre , Prolactina/sangre , Estaciones del Año , Animales , Femenino , Periodo Posparto/sangre , Embarazo , Progesterona/sangre
17.
J Comp Pathol ; 96(5): 587-91, 1986 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3760270

RESUMEN

Isoelectric focusing and gradient polyacrylamide gel electrophoresis were used to define the physical differences between canine liver alkaline phosphatase (LAP) and steroid induced alkaline phosphatase (SIAP). LAP has an isoelectric point (pI) of pH 4.3 and a molecular radius (Mr) of 100,000, while SIAP has a pI of pH 3.5 and an Mr of 110,000. After removal of sialic acid residues by neuraminidase, the two isoenzymes were still distinct. The pIs of both LAP and SIAP were increased with the pI of LAP becoming pH 4.7 to 4.8 and that of SIAP becoming pH 4.5 to 4.6. On gradient polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate, SIAP gave a single band of Mr 100 000 after neuraminidase treatment, while LAP increased in molecular size in spite of the denaturing conditions of the electrophoretic separation.


Asunto(s)
Fosfatasa Alcalina/sangre , Perros/sangre , Isoenzimas/sangre , Neuraminidasa/farmacología , Animales , Punto Isoeléctrico , Peso Molecular , Esteroides/metabolismo
18.
Res Vet Sci ; 41(1): 126-8, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3489967

RESUMEN

The levels of three plasma proteins, which are classed as acute phase reactants, were compared in a group of cows which suffered from mastitis with those in a group of cows which were clinically normal. The plasma levels of haptoglobin, ceruloplasmin and alpha 1 antitrypsin were higher in the cows with mastitis than in normal cows.


Asunto(s)
Ceruloplasmina/análisis , Haptoglobinas/análisis , Mastitis Bovina/sangre , alfa 1-Antitripsina/análisis , Animales , Bovinos , Femenino
19.
J Reprod Fertil ; 77(2): 569-74, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3755475

RESUMEN

Five pony mares were blood sampled during late pregnancy, foaling and early lactation. An homologous assay for horse prolactin was used to measure plasma prolactin concentrations in these samples. Regular estimates of cyclic activity were also made. Plasma prolactin concentrations rose markedly in the last week of pregnancy and remained high although variable in early lactation, before declining to basal levels by 1-2 months post partum. All mares showed a post-partum oestrus 7.0 +/- 0.9 days after parturition. One mare whose foal died shortly after birth showed a rapid decline in plasma prolactin values after death of the foal and an early oestrous period (4 days after parturition). The pattern of prolactin changes reported for the mare are in agreement with those reported for other mammalian species.


Asunto(s)
Caballos/sangre , Trabajo de Parto , Lactancia , Preñez , Prolactina/sangre , Animales , Estro , Femenino , Embarazo
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