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1.
Appl Microbiol Biotechnol ; 101(10): 4299-4314, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28190100

RESUMO

Coastal sediments contaminated by polycyclic aromatic hydrocarbons (PAHs) can be candidates for remediation via an approach like land farming. Land farming converts naturally anaerobic sediments to aerobic environments, and the response of microbial communities, in terms of community structure alterations and corresponding effects on biodegradative activities, is unknown. A key goal of this study was to determine if different sediments exhibited common patterns in microbial community responses that might serve as indicators of PAH biodegradation. Sediments from three stations in the Lagos Lagoon (Nigeria) were used in microcosms, which were spiked with a mixture of four PAH, then examined for PAH biodegradation and for shifts in microbial community structure by analysis of diversity in PAH degradation genes and Illumina sequencing of 16S rRNA genes. PAH biodegradation was similar in all sediments, yet each exhibited unique microbiological responses and there were no microbial indicators of PAH bioremediation common to all sediments.


Assuntos
Biodegradação Ambiental , Estuários , Sedimentos Geológicos/microbiologia , Consórcios Microbianos/fisiologia , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes Químicos da Água/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Consórcios Microbianos/genética , Nigéria , Fenantrenos/metabolismo , Pirenos/metabolismo , RNA Ribossômico 16S/genética , Poluentes do Solo/metabolismo
2.
Proc Natl Acad Sci U S A ; 110(25): 10111-6, 2013 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-23729815

RESUMO

Although the field of microfluidics has made significant progress in bringing new tools to address biological questions, the accessibility and adoption of microfluidics within the life sciences are still limited. Open microfluidic systems have the potential to lower the barriers to adoption, but the absence of robust design rules has hindered their use. Here, we present an open microfluidic platform, suspended microfluidics, that uses surface tension to fill and maintain a fluid in microscale structures devoid of a ceiling and floor. We developed a simple and ubiquitous model predicting fluid flow in suspended microfluidic systems and show that it encompasses many known capillary phenomena. Suspended microfluidics was used to create arrays of collagen membranes, mico Dots (µDots), in a horizontal plane separating two fluidic chambers, demonstrating a transwell platform able to discern collective or individual cellular invasion. Further, we demonstrated that µDots can also be used as a simple multiplexed 3D cellular growth platform. Using the µDot array, we probed the combined effects of soluble factors and matrix components, finding that laminin mitigates the growth suppression properties of the matrix metalloproteinase inhibitor GM6001. Based on the same fluidic principles, we created a suspended microfluidic metabolite extraction platform using a multilayer biphasic system that leverages the accessibility of open microchannels to retrieve steroids and other metabolites readily from cell culture. Suspended microfluidics brings the high degree of fluidic control and unique functionality of closed microfluidics into the highly accessible and robust platform of open microfluidics.


Assuntos
Técnicas Analíticas Microfluídicas , Microfluídica/instrumentação , Microfluídica/métodos , Modelos Biológicos , Córtex Suprarrenal/citologia , Neoplasias da Mama/patologia , Capilares/metabolismo , Biologia Celular/instrumentação , Linhagem Celular Tumoral , Membrana Celular/fisiologia , Movimento Celular , Colágeno Tipo I/metabolismo , Simulação por Computador , Feminino , Humanos , Hidrocortisona/análise , Hidrocortisona/metabolismo , Masculino , Inibidores de Metaloproteinases de Matriz/farmacologia , Metabolômica/instrumentação , Metabolômica/métodos , Neoplasias da Próstata/patologia , Esteroides/análise , Esteroides/metabolismo , Toxicologia/instrumentação , Toxicologia/métodos
3.
J Environ Qual ; 45(5): 1776-1781, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27695756

RESUMO

Hormone contamination of aquatic systems has been shown to have deleterious effects on aquatic biota. However, the assessment of hormone contamination of aquatic environments requires a quantitative evaluation of the potential effects of sample preservation on hormone concentrations. This study investigated the influence of acidification (pH 2) of surface water samples on the partitioning of hormones among filtrate, filter media, and filter-retained particulate matter. Hormones were spiked into unpreserved and sulfuric acid-preserved ultrapure water and surface water runoff samples. The samples were filtered, and hormones were extracted from the filter and filtrate and analyzed by high-performance liquid chromatography. Acidification did not influence the partitioning of hormones onto the filter media. For the majority of the hormones investigated in this study, the partitioning of hormones to the filter-retained particulate matter was not influenced by acidification. Acidification increased the partitioning of progesterone and melengestrol acetate onto the retained particulate matter (about 25% for both analytes). Incorporation of an isotopically labeled internal standard (ISTD) for progesterone accounted for the loss of progesterone to the filter-retained particulates and resulted in accurate concentrations of progesterone in the filtrate. The incorporation of an ISTD for melengestrol acetate, however, was unable to account for the loss of melengestrol acetate to the retained particulates and resulted in underestimations of melengestrol acetate in the filtrate. Our results indicate that the analysis of melengestrol acetate in acid preserved surface runoff samples should be conducted on the filter-retained particulates as well as the filtrate.


Assuntos
Hormônios/análise , Poluentes Químicos da Água/análise , Filtração , Material Particulado , Movimentos da Água
4.
Am J Primatol ; 77(7): 801-10, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25845705

RESUMO

Vitamin D metabolites are widely studied for their roles in bone health, immune functions, and other potential physiologic roles in humans. However, the optimal blood levels of vitamin D metabolites are still unclear. Various methods for measuring vitamin D metabolites have been used and recently liquid chromatography tandem mass spectroscopy (LC-MS/MS) has been adopted as the gold standard for vitamin D metabolite measurement. Here, we report the use of LC-MS/MS to measure 25-hydroxyvitamin D (25(OH)D(2&3)), and 1,25-dihydroxyvitamin D (1,25(OH)2D(2&3)), in three laboratory nonhuman primate species: common marmoset (Callithrix jacchus), rhesus macaque (Macaca mulatta), and cynomolgus macaque (Macaca fascicularis), and compare them to humans using the same technique. The nonhuman primates showed blood levels for 25(OH)D3 and 1,25(OH)2D3 significantly higher than human values with marmosets having the highest levels. Marmoset samples showed significantly more variability among individuals than those from macaques for both metabolites, but all three nonhuman primate species exhibited large variation within species for both 25(OH)D(2&3) and 1,25(OH)2D(2&3). Marmoset females had significantly lower values than the males for 25(OH)D3, while rhesus males showed a significant decrease in 25(OH)D3 with age. The most striking finding is the variation within species for vitamin D levels even in laboratory primates that have a controlled diet, UV exposure, and in some cases, genetic constraints. Similar variation in 25(OH)D responses to a fixed dose of oral vitamin D supplementation has been reported in humans. We suggest that these species can provide primate models for examining the factors influencing variation in the levels of vitamin D necessary for human and nonhuman primate health.


Assuntos
Callithrix/sangue , Macaca fascicularis/sangue , Macaca mulatta/sangue , Vitamina D/análogos & derivados , Fatores Etários , Animais , Cromatografia Líquida , Feminino , Humanos , Masculino , Fatores Sexuais , Especificidade da Espécie , Espectrometria de Massas em Tandem , Vitamina D/sangue
5.
Pediatr Res ; 75(4): 476-81, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24418932

RESUMO

BACKGROUND: It is established that maternal parity can affect infant growth and risk for several disorders, but the prenatal endocrine milieu that contributes to these outcomes is still largely unknown. Recently, it has been shown that hormones deposited in hair can provide a retrospective reflection of hormone levels while the hair was growing. Taking advantage of this finding, our study utilized hair at birth to investigate if maternal parity affected fetal hormone exposure during late gestation. METHODS: Hair was collected from primiparous and multiparous mother and infant monkeys at birth and used to determine steroid hormones embedded in hair while the infant was in utero. A high-pressure liquid chromatography-triple quadrupole mass spectrometry technique was refined, which enabled the simultaneous measurement of eight hormones. RESULTS: Hormone concentrations were dramatically higher in neonatal compared to maternal hair, reflecting extended fetal exposure as the first hair was growing. Further, hair cortisone was higher in primiparous mothers and infants when compared to the multiparous dyads. CONCLUSION: This research demonstrates that infant hair can be used to track fetal hormone exposure and a panel of steroid hormones can be quantified from hair specimens. Given the utility in nonhuman primates, this approach can be translated to a clinical setting with human infants.


Assuntos
Animais Recém-Nascidos , Cabelo/química , Hormônios/análise , Animais , Cromatografia Líquida de Alta Pressão , Feminino , Macaca mulatta/embriologia , Masculino , Fatores Sexuais
6.
J Forensic Sci ; 69(3): 1011-1020, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38351585

RESUMO

Recreational methamphetamine production and heavy use can result in dwelling contamination that is difficult to detect. First responders and public health officials may use commercially available trace methamphetamine detection (presumptive) test kits to understand apparent and hidden dangers in impacted dwellings. Here, we assessed the limit of detection (LOD) of several commercially available presumptive test kits using simulated contaminated hard surfaces. Pyrex petri dishes were spiked with aliquots of methanolic methamphetamine solutions to reach desired simulated contamination levels. Commercially available presumptive tests were conducted according to manufacturer instructions and using included sample preparation materials, when available. Additionally, a laboratory-based liquid chromatography-triple quadrupole mass spectrometer (LC-MS/MS) trace methamphetamine quantification method was developed and validated using the EZSTATSG2 tool. For the LC-MS/MS method, samples were collected using 2-ply alcohol prep pads and methamphetamine was extracted using a 1:1 (v:v) methanol: water solution. Most presumptive tests considered were able to detect trace levels of methamphetamine extracted from hard surfaces, with LOD ranging from 0.10-15.00 µg/sample. Comparatively, the laboratory-based LC-MS/MS LOD was 0.05 µg/sample and limit of quantitation was 0.10 µg/sample. The LC-MS/MS method may be useful when the presence of dust or other contaminants interferes with presumptive test interpretation or reliability. Costs of presumptive tests varied from several dollars to tens of dollars, which is included alongside LOD results to aid stakeholders in identifying which test(s) are the best fit for purpose. Therefore, first responders, public health officials, and other stakeholders have several options for assessing trace methamphetamine contamination.


Assuntos
Toxicologia Forense , Limite de Detecção , Metanfetamina , Metanfetamina/análise , Cromatografia Líquida , Humanos , Toxicologia Forense/métodos , Estimulantes do Sistema Nervoso Central/análise , Espectrometria de Massas em Tandem , Propriedades de Superfície , Espectrometria de Massas/métodos , Espectrometria de Massa com Cromatografia Líquida
7.
Breast Cancer Res ; 15(3): R45, 2013 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-23710608

RESUMO

INTRODUCTION: Humans are widely exposed to estrogenically active phthalates, parabens, and phenols, raising concerns about potential effects on breast tissue and breast cancer risk. We sought to determine the association of circulating serum levels of these chemicals (reflecting recent exposure) with mammographic breast density (a marker of breast cancer risk). METHODS: We recruited postmenopausal women aged 55 to 70 years from mammography clinics in Madison, Wisconsin (N = 264). Subjects completed a questionnaire and provided a blood sample that was analyzed for mono-ethyl phthalate, mono-butyl phthalate, mono-benzyl phthalate, butyl paraben, propyl paraben, octylphenol, nonylphenol, and bisphenol A (BPA). Percentage breast density was measured from mammograms by using a computer-assisted thresholding method. RESULTS: Serum BPA was positively associated with mammographic breast density after adjusting for age, body mass index, and other potentially confounding factors. Mean percentage density was 12.6% (95% confidence interval (CI), 11.4 to 14.0) among the 193 women with nondetectable BPA levels, 13.7% (95% CI, 10.7 to 17.1) among the 35 women with detectable levels below the median (<0.55 ng/ml), and 17.6% (95% CI, 14.1 to 21.5) among the 34 women with detectable levels above the median (>0.55 ng/ml; Ptrend = 0.01). Percentage breast density was also elevated (18.2%; 95% CI, 13.4 to 23.7) among the 18 women with serum mono-ethyl phthalate above the median detected level (>3.77 ng/ml) compared with women with nondetectable BPA levels (13.1%; 95% CI, 11.9 to 14.3; Ptrend = 0.07). No other chemicals demonstrated associations with percentage breast density. CONCLUSIONS: Postmenopausal women with high serum levels of BPA and mono-ethyl phthalate had elevated breast density. Further investigation of the impact of BPA and mono-ethyl phthalate on breast cancer risk by using repeated serum measurements or other markers of xenoestrogen exposure are needed.


Assuntos
Neoplasias da Mama/sangue , Estrogênios/sangue , Glândulas Mamárias Humanas/anormalidades , Idoso , Compostos Benzidrílicos/sangue , Densidade da Mama , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Feminino , Humanos , Mamografia , Pessoa de Meia-Idade , Fenóis/sangue , Ácidos Ftálicos/sangue , Pós-Menopausa/sangue
8.
Nutr Cancer ; 64(6): 783-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22860715

RESUMO

Some forms of estrogen are associated with breast cancer risk as well as with mammographic density (MD), a strong marker of breast cancer risk. Whether phytoestrogen intake affects breast density, however, remains unclear. We evaluated the association between serum levels of phytoestrogens and MD in postmenopausal women. We enrolled 269 women, ages 55-70 yr, who received a screening mammogram and had no history of postmenopausal hormone use. Subjects completed a survey on diet and factors related to MD and provided a blood sample for analysis of 3 phytoestrogens: genistein, daidzein, and coumestrol. We examined whether mean percent MD was related to serum level of phytoestrogens, adjusting for age and body mass index. Genistein and daidzein levels correlated with self-reported soy consumption. Mean percent MD did not differ across women with different phytoestrogen levels. For example, women with nondetectable genistein levels had mean density of 11.0% [95% confidence intervals (CI) = 9.9-12.4], compared to 10.5% (95% CI = 8.0-13.7) and 11.2% (95% CI = 8.7-14.6) for < and ≥ median detectable levels, respectively. In a population with relatively low soy intake, serum phytoestrogens were not associated with mammographic density. Additional studies are needed to determine effects of higher levels, particularly given patterns of increasing phytoestrogen intake.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Cumestrol/sangue , Genisteína/sangue , Isoflavonas/sangue , Idoso , Índice de Massa Corporal , Dieta , Comportamento Alimentar , Feminino , Humanos , Mamografia , Pessoa de Meia-Idade , Pós-Menopausa , Glycine max
9.
Environ Sci Technol ; 46(5): 2642-51, 2012 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-22243052

RESUMO

The transformation of the sulfonamide antimicrobial sulfamethazine (SMZ) by a synthetic analogue of the birnessite-family mineral vernadite (δ-MnO(2)) was studied. The observed pseudo-first-order reaction constants (k(obs)) decreased as the pH increased from 4.0 to 5.6, consistent with the decline in δ-MnO(2) reduction potential with increasing pH. Molecular oxygen accelerated SMZ transformation by δ-MnO(2) and influenced the transformation product distribution. Increases in the Na(+) concentration produced declines in k(obs). Transformation products identified by tandem mass spectrometry and the use of (13)C-labeled SMZ included an azo dimer self-coupling product and SO(2) extrusion products. Product analysis and density functional theory calculations are consistent with surface precursor complex formation followed by single-electron transfer from SMZ to δ-MnO(2) to produce SMZ radical species. Sulfamethazine radicals undergo further transformation by at least two pathways: radical-radical self-coupling or a Smiles-type rearrangement with O addition and then extrusion of SO(3). Experiments conducted in H(2)(18)O or in the presence of (18)O(2)(aq) demonstrated that oxygen both from the lattice of as-synthesized δ-MnO(2) and initially present as dissolved oxygen reacted with SMZ. The study results suggest that the oxic state and pH of soil and sediment environments can be expected to influence manganese oxide-mediated transformation of sulfonamide antimicrobials.


Assuntos
Compostos de Manganês/química , Óxidos/química , Sulfametazina/química , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Cinética , Espectrometria de Massas , Oxigênio/química , Sódio/química , Soluções , Termodinâmica
10.
Environ Sci Technol ; 45(15): 6468-74, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-21682266

RESUMO

Organosulfates have been proposed as contributors to aerosol growth and have been detected in both chamber and atmospheric aerosol samples. We present a simple method for the synthesis of quantitative analytical standards of two small hydroxycarboxylic acid-derived organosulfates, glycolic and lactic acid sulfate. Additionally, we discuss the stability of hydroxycarboxylic acid-derived organosulfates and their previously proposed sulfate hemiacetal isomers in commonly used solvents for filter extraction. The hydroxycarboxylic acid-derived organosulfates were found to be stable under acidic conditions comparable to those found in ambient aerosol. By using synthesized standards, quantitative organosulfate concentrations were measured from ambient particulate matter (PM(2.5)) collected in urban locations in the United States, Mexico City, and Pakistan. Lactic acid sulfate and glycolic acid sulfate concentrations ranged 0.4-3.8 ng/m(3) and 1.9-11.3 ng/m(3), respectively. We propose that glycolic acid sulfate represents an important tracer for atmospheric processes that form organosulfates in ambient particulate matter.


Assuntos
Ácidos Carboxílicos/química , Ácidos Carboxílicos/síntese química , Material Particulado/análise , Sulfatos/química , Sulfatos/síntese química , Acetais/química , Carbono/análise , Cromatografia Líquida , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Padrões de Referência
11.
J Toxicol Environ Health A ; 74(17): 1150-74, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21797769

RESUMO

Questions have been raised regarding possible exposures when playing sports on synthetic turf fields cushioned with crumb rubber. Rubber is a complex mixture with some components possessing toxic and carcinogenic properties. Exposure is possible via inhalation, given that chemicals emitted from rubber might end up in the breathing zone of players and these players have high ventilation rates. Previous studies provide useful data but are limited with respect to the variety of fields and scenarios evaluated. The State of Connecticut investigated emissions associated with four outdoor and one indoor synthetic turf field under summer conditions. On-field and background locations were sampled using a variety of stationary and personal samplers. More than 20 chemicals of potential concern (COPC) were found to be above background and possibly field-related on both indoor and outdoor fields. These COPC were entered into separate risk assessments (1) for outdoor and indoor fields and (2) for children and adults. Exposure concentrations were prorated for time spent away from the fields and inhalation rates were adjusted for play activity and for children's greater ventilation than adults. Cancer and noncancer risk levels were at or below de minimis levels of concern. The scenario with the highest exposure was children playing on the indoor field. The acute hazard index (HI) for this scenario approached unity, suggesting a potential concern, although there was great uncertainty with this estimate. The main contributor was benzothiazole, a rubber-related semivolatile organic chemical (SVOC) that was 14-fold higher indoors than outdoors. Based upon these findings, outdoor and indoor synthetic turf fields are not associated with elevated adverse health risks. However, it would be prudent for building operators to provide adequate ventilation to prevent a buildup of rubber-related volatile organic chemicals (VOC) and SVOC at indoor fields. The current results are generally consistent with the findings from studies conducted by New York City, New York State, the U.S. Environmental Protection Agency (EPA), and Norway, which tested different kinds of fields and under a variety of weather conditions.


Assuntos
Poluentes Atmosféricos/toxicidade , Carcinógenos Ambientais/toxicidade , Elastômeros/toxicidade , Exposição Ambiental/efeitos adversos , Jogos e Brinquedos , Logradouros Públicos , Equipamentos Esportivos/efeitos adversos , Adulto , Fatores Etários , Poluentes Atmosféricos/normas , Poluição do Ar em Ambientes Fechados/efeitos adversos , Atletas , Benzotiazóis/administração & dosagem , Benzotiazóis/análise , Benzotiazóis/toxicidade , Carcinógenos Ambientais/administração & dosagem , Carcinógenos Ambientais/normas , Criança , Connecticut/epidemiologia , Elastômeros/química , Elastômeros/economia , Exposição Ambiental/normas , Arquitetura de Instituições de Saúde/economia , Guias como Assunto , Humanos , Neoplasias/epidemiologia , Logradouros Públicos/economia , Reciclagem , Taxa Respiratória , Medição de Risco , Fatores de Risco , Estações do Ano , Equipamentos Esportivos/economia
12.
J Toxicol Environ Health A ; 74(17): 1133-49, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21797768

RESUMO

The primary purpose of this study was to characterize the concentrations of volatile organic compounds (VOC), semivolatile organic compounds (SVOC), rubber-related chemicals such as benzothiazole (BZT) and nitrosamine, and particulate matter (PM(10)) in air at synthetic turf crumb rubber fields. Both new and older fields were evaluated under conditions of active use. Three types of fields were targeted: four outdoor crumb rubber fields, one indoor facility with crumb rubber turf, and an outdoor natural grass field. Background samples were collected at each field on grass. Personal air sampling was conducted for VOC, BZT, nitrosamines, and other chemicals. Stationary air samples were collected at different heights to assess the vertical profile of release. Air monitoring for PM(10) was conducted at one height. Bulk samples of turf grass and crumb rubber were analyzed, and meteorological data were recorded. Results showed that personal concentrations were higher than stationary concentrations and were higher on turf than in background samples for certain VOC. In some cases, personal VOC concentrations from natural grass fields were as high as those on turf. Naphthalene, BZT, and butylated hydroxytoluene (BHT) were detected in greater concentration at the indoor field compared to the outdoor fields. Nitrosamine air levels were below reporting levels. PM(10) air concentrations were not different between on-field and upwind locations. All bulk lead (Pb) samples were below the public health target of 400 ppm. More research is needed to better understand air quality at indoor facilities. These field investigation data were incorporated into a separate human health risk assessment.


Assuntos
Poluentes Atmosféricos/análise , Elastômeros/química , Jogos e Brinquedos , Logradouros Públicos , Equipamentos Esportivos/efeitos adversos , Poluentes Atmosféricos/normas , Poluição do Ar em Ambientes Fechados/análise , Altitude , Benzotiazóis/análise , Hidroxitolueno Butilado/análise , Connecticut , Elastômeros/economia , Elastômeros/toxicidade , Arquitetura de Instituições de Saúde/economia , Chumbo/análise , Naftalenos/análise , Nitrosaminas/análise , Material Particulado/análise , Poaceae/química , Logradouros Públicos/economia , Prática de Saúde Pública , Reciclagem , Estações do Ano , Equipamentos Esportivos/economia , Compostos Orgânicos Voláteis/análise
13.
Sci Total Environ ; 710: 136247, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-31923660

RESUMO

Hormone contamination of aquatic systems has been shown to cause reproductive impairment of aquatic organisms. To assess to what extent beef and dairy farms represent a source of hormones to the aquatic environment, surface water runoff samples from three beef and dairy farms that utilize best manure management practices were evaluated for hormone concentrations (estrogens, androgens, progestogens) and estrogenic activity. Runoff was collected from weirs at the edge of each of six study fields from March 2008 to March 2010 and was analyzed for hormone concentrations using liquid chromatography with tandem mass spectrometry and for estrogenic activity using the E-screen bioassay. The majority of runoff events occurred in February and March when the soil was frozen. Progesterone and 4-androstenedione were the most frequently detected hormones (63% and 50%, respectively) and occurred at event loads up to 49,000 µg/ha and 26,000 µg/ha, respectively. Progesterone, 4-androstenedione, 17α-estradiol had the highest event load concentrations and were found at the field that sustained dairy cattle grazing during the winter and were likely due to application of excreta on frozen soil. The high progesterone event loads could lead to concentrations in receiving streams that exceed the lowest observable effects concentrations for fish. There was a consistent association with the elevated zearalenone presence and corn production. The synthetic hormones, 17α-trenbolone and 17ß-trenbolone, were not detected in runoff from the beef farm that utilized trenbolone acetate implants, which is likely due to their short half lives. Estrogenic activity in runoff samples ranged from 0.09 to 133 ng/L estradiol equivalents, with 39% of runoff events exceeding the 2 ng/L predicted-no-effect-concentration for fish. These results indicate that grazing cattle and application of manure to frozen fields present the greatest risk to elevated hormones in runoff and that progesterone is the primary hormone of concern from beef and dairy operations.


Assuntos
Carne Vermelha , Androgênios , Animais , Bovinos , Estrogênios , Esterco , Progestinas , Água , Poluentes Químicos da Água
14.
J Environ Qual ; 38(1): 149-56, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19141804

RESUMO

The detection of pharmaceuticals and other organic wastewater contaminants (OWCs) in ground water and surface-water bodies has raised concerns about the possible ecological impacts of these compounds on nontarget organisms. On-site wastewater treatment systems represent a potentially significant route of entry for organic contaminants to the environment. In this study, effluent samples were collected and analyzed from conventional septic systems and from systems using advanced treatment technologies. Six of 13 target compounds were detected in effluent from at least one septic system. Caffeine, paraxanthine, and acetaminophen were the most frequently detected compounds, and estrogenic activity was detected in 14 of 15 systems. The OWC concentrations were significantly lower in effluent after sand filtration (p < 0.01) or aerobic treatment (p < 0.05) as compared with effluent that had not undergone advanced treatment. In general, concentrations in conventional systems were comparable to those measured in previous studies of municipal wastewater treatment plant (WWTP) influent, and concentrations in systems after advanced treatment were comparable to previously measured concentrations in WWTP effluent. These data indicate that septic systems using advanced treatment can reduce OWCs in treated effluent to similar concentrations as municipal WWTPs.


Assuntos
Compostos Orgânicos/análise , Gerenciamento de Resíduos/métodos , Poluentes Químicos da Água/análise , Acetaminofen/análise , Cafeína/análise , Cromatografia Líquida , Disruptores Endócrinos/análise , Espectrometria de Massas em Tandem , Teofilina/análise , Fatores de Tempo
16.
J Environ Qual ; 37(5): 1817-24, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18689743

RESUMO

The presence and levels of the cyanobacterial toxins microcystin-LR, anatoxin-a, and cylindrospermopsin were measured in various Wisconsin waters where algal nuisance or bloom conditions were noted. Out of 74 samples analyzed, 36 had detectable levels of microcystin-LR (49%), and four had detectable levels of anatoxin-a (5%). Cylindrospermopsin, the toxin produced by Cylindrospermopsis (a warm water species that has been moving its range northward, including to Wisconsin), was not detected in the field samples tested. Concentrations of microcystin-LR ranged from 1.2 to 7600 microg L(-1). Anatoxin-a ranged from 0.68 to 1750 microg L(-1), which is the highest concentration reported from around the world. Cyanobacterial toxins, because of their high potency, deserve continued scrutiny by resource managers and public health officials responsible for recreational waters.


Assuntos
Toxinas Bacterianas/análise , Cromatografia Líquida de Alta Pressão , Água Doce/química , Toxinas Marinhas/análise , Microcistinas/análise , Espectrometria de Massas em Tandem , Toxinas de Cianobactérias , Eutrofização , Estrutura Molecular
17.
Water Res ; 140: 280-290, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29729580

RESUMO

Freshwater cyanobacterial blooms are becoming increasingly problematic in regions that rely on surface waters for drinking water production. Microcystins (MCs) are toxic peptides produced by multiple cyanobacterial genera with a global occurrence. Cyanobacteria also produce a variety of other toxic and/or otherwise bioactive peptides (TBPs) that have gained less attention including cyanopeptolins (Cpts), anabaenopeptins (Apts), and microginins (Mgn). In this study, we compared temporal and spatial trends of four MCs (MCLR, MCRR, MCYR, MCLA), three Cpts (Cpt1020, Cpt1041, Cpt1007), two Apts (AptF, AptB), and Mgn690 in raw drinking water and at six surface water locations above these drinking water intakes in a eutrophic lake. All four MC congeners and five of six TBPs were detected in lake and raw drinking water. Across all samples, MCLR was the most frequently detected metabolite (100% of samples) followed by MCRR (97%) > Cpt1007 (74%) > MCYR (69%) > AptF (67%) > MCLA (61%) > AptB (54%) > Mgn690 (29%) and Cpt1041 (15%). Mean concentrations of MCs, Apts, and Cpts into two drinking water intakes were 3.9 ±â€¯4.7, 0.14 ±â€¯0.21, and 0.38 ±â€¯0.92, respectively. Mean concentrations in surface water were significantly higher (p < 0.05) than in drinking water intakes for MCs but not for Cpts and Apts. Temporal trends in MCs, Cpts, and Apts in the two raw drinking water intakes were significantly correlated (p < 0.05) with measures of cell abundance (chlorophyll-a, Microcystis cell density), UV absorbance, and turbidity in surface water. This study expands current information about cyanobacterial TBPs that occur in lakes and that enter drinking water treatment plants and underscores the need to determine the fate of less studied cyanobacterial metabolites during drinking water treatment that may exacerbate toxicity of more well-known cyanobacterial toxins.


Assuntos
Cianobactérias/metabolismo , Lagos/microbiologia , Microbiologia da Água , Toxinas Bacterianas/análise , Clorofila/análise , Clorofila/metabolismo , Clorofila A , Toxinas de Cianobactérias , Depsipeptídeos , Água Potável , Lagos/análise , Toxinas Marinhas/análise , Microcistinas/análise , Microcystis/metabolismo , Peptídeos Cíclicos/análise , Peptídeos Cíclicos/metabolismo , Análise Espaço-Temporal , Wisconsin
18.
J Am Soc Mass Spectrom ; 18(5): 817-25, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17337345

RESUMO

Beta-methylamino-L-alanine (BMAA) is a neurotoxic amino acid that can be produced by cyanobacteria in aqueous environments. To analyze this compound by gas chromatography/mass spectrometry (GC/MS), BMAA must be derivatized to a nonpolar, volatile compound. This can be accomplished by reacting BMAA with ethyl chloroformate. While carrying out electron ionization (EI) mass spectrometric analysis on the (13)C-labeled derivative, it was discovered that the formation of an ion with a peak at m/z 245.12 is the result of [CH(3)CH(2)O.] loss from the amino groups resulting from alpha-cleavage. This differs from previous reports that attributed this peak to alpha-cleavage of the carboxylic ester portion of the BMAA derivative. This finding is important for understanding BMAA derivative mass spectrometric fragmentation patterns and ultimately to properly identifying and quantifying BMAA. Fragmentation pathways for the formation of other major peaks observed in the EI mass spectra are also proposed.


Assuntos
Diamino Aminoácidos/química , Ésteres do Ácido Fórmico/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Toxinas de Cianobactérias , Espectrometria de Massas por Ionização por Electrospray
19.
Biomaterials ; 101: 20-31, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27267625

RESUMO

Triple negative breast cancer (TNBC) is an aggressive subtype of breast cancer for which there is no available targeted therapy. TNBC cases contribute disproportionately to breast cancer-related mortality, thus the need for novel and effective therapeutic methods is urgent. We have previously shown that a National Cancer Institute (NCI) investigational drug aminoflavone (AF) exhibits strong growth inhibitory effects in TNBC cells. However, in vivo pulmonary toxicity resulted in withdrawal or termination of several human clinical trials for AF. Herein we report the in vivo efficacy of a nanoformulation of AF that enhances the therapeutic index of AF in TNBC. We engineered a unique unimolecular micelle nanoparticle (NP) loaded with AF and conjugated with GE11, a 12 amino acid peptide targeting epidermal growth factor receptor (EGFR), since EGFR amplification is frequently observed in TNBC tumors. These unimolecular micelles possessed excellent stability and preferentially released drug payload at endosomal pH levels rather than blood pH levels. Use of the GE11 targeting peptide resulted in enhanced cellular uptake and strong growth inhibitory effects in TNBC cells. Further, AF-loaded, GE11-conjugated (targeted) unimolecular micelle NPs significantly inhibit orthotopic TNBC tumor growth in a xenograft model, compared to treatment with AF-loaded, GE11-lacking (non-targeted) unimolecular micelle NPs or free AF. Interestingly, the animals treated with AF-loaded, targeted NPs had the highest plasma and tumor level of AF among different treatment groups yet exhibited no increase in plasma aspartate aminotransferase (AST) activity level or observable tissue damage at the time of sacrifice. Together, these results highlight AF-loaded, EGFR-targeted unimolecular micelle NPs as an effective therapeutic option for EGFR-overexpressing TNBC.


Assuntos
Antineoplásicos/administração & dosagem , Portadores de Fármacos/química , Receptores ErbB/metabolismo , Flavonoides/administração & dosagem , Nanopartículas/química , Peptídeos/química , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Mama/efeitos dos fármacos , Mama/metabolismo , Mama/patologia , Linhagem Celular Tumoral , Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos , Feminino , Flavonoides/farmacocinética , Flavonoides/uso terapêutico , Humanos , Micelas , Nanopartículas/metabolismo , Nanopartículas/ultraestrutura , Peptídeos/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
20.
Sci Total Environ ; 554-555: 178-85, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26950631

RESUMO

Green eco-friendly housing includes approaches to reduce indoor air pollutant sources and to increase energy efficiency. Although sealing/tightening buildings can save energy and reduce the penetration of outdoor pollutants, an adverse outcome can be increased buildup of pollutants with indoor sources. The objective of this study was to determine the differences in the indoor air quality (IAQ) between green and non-green homes in low-income housing complexes. In one housing complex, apartments were renovated using green principles (n=28). Home visits were conducted immediately after the renovation, and subsequently at 6 months and at 12 months following the renovation. Of these homes, eight homes had pre-renovation home visits; this allowed pre- and post-renovation comparisons within the same homes. Parallel visits were conducted in non-green (control) apartments (n=14) in a nearby low-income housing complex. The IAQ assessments included PM2.5, black carbon, ultrafine particles, sulfur, total volatile organic compounds (VOCs), formaldehyde, and air exchange rate. Data were analyzed using linear mixed-effects models. None of the indoor pollutant concentrations were significantly different between green and non-green homes. However, we found differences when comparing the concentrations before and after renovation. Measured immediately after renovation, indoor black carbon concentrations were significantly lower averaging 682 ng/m(3) in post-renovation vs. 2364 ng/m(3) in pre-renovation home visits (p=0.01). In contrast, formaldehyde concentrations were significantly higher in post-renovated (0.03 ppm) than in pre-renovated homes (0.01 ppm) (p=0.004). Questionnaire data showed that opening of windows occurred less frequently in homes immediately post-renovation compared to pre-renovation; this factor likely affected the levels of indoor black carbon (from outdoor sources) and formaldehyde (from indoor sources) more than the renovation status itself. To reduce IAQ problems and potentially improve health, careful selection of indoor building materials and ensuring sufficient ventilation are important for green building designs.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Exposição Ambiental/estatística & dados numéricos , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Criança , Conservação dos Recursos Naturais , Materiais de Construção , Monitoramento Ambiental , Formaldeído/análise , Humanos , Ohio , Pobreza , Compostos Orgânicos Voláteis/análise
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