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1.
Chemosphere ; 85(5): 717-23, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21722939

RESUMEN

Bankside groundwater is widely used as drinking water resource and, therefore, contamination has to be avoided. In the European Union groundwater protection is explicit subject to Water Framework Directive. While groundwater pollution may originate from different sources, this study investigated on impacts via flood events. Groundwater was sampled with increasing distance to the river Rhine near Karlsruhe, Germany. Samples were HPLC-MS-MS analyzed for the river contaminant carbamazepine to indicate river water infiltration, giving permanent presence in 250 m distance to the river (14-47 µg L⁻¹). Following a flood event, concentrations of about 16-20 µg L⁻¹ could also be detected in a distance of 750 m to the river. Furthermore, estrogenic activity as determined with the Yeast Estrogen Screen assay was determined to increase up to a 17ß-ethinylestradiol equivalent concentration (E-EQ)=2.9 ng L⁻¹ near the river, while activity was initially measured following the flood with up to E-EQ=2.6 ng L⁻¹ in 750 m distance. Detections were delayed with increasing distance to the river indicating river water expansion into the aquifer. Flood suspended matter and floodplain soil were fractionated and analyzed for estrogenic activity in parallel giving up to 1.4 ng g⁻¹ and up to 0.7 ng g⁻¹, respectively. Target analysis focusing on known estrogenic active substances only explained < 1% of measured activities. Nevertheless, river water infiltration was shown deep into bankside groundwater, thus, impacting groundwater quality. Therefore, flood events have to be in the focus when aiming for groundwater and drinking water protection as well as for implementation of Water Framework Directive.


Asunto(s)
Estrógenos/análisis , Inundaciones , Agua Subterránea/análisis , Material Particulado/análisis , Suelo/análisis , Contaminantes Químicos del Agua/análisis , Analgésicos no Narcóticos/análisis , Carbamazepina/análisis , Monitoreo del Ambiente/métodos , Alemania , Ríos/química
2.
J Antimicrob Chemother ; 60(1): 100-6, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17525052

RESUMEN

BACKGROUND: Co-morbidity, medical and surgical interventions often cause alterations to drug plasma concentrations and pharmacokinetic parameters in critically ill patients. In the present study, we investigated parameters influencing plasma caspofungin concentrations in patients of a surgical intensive care unit (SICU). METHODS: In a monocentre open study, caspofungin trough concentrations (C(24)) were determined for a group of SICU patients. A linear-mixed model was then used to assess factors influencing caspofungin plasma concentrations. RESULTS: A total of 40 SICU patients were enrolled. Age and body weight ranged from 22 to 76 years and 47 to 108 kg, respectively. All participants received a caspofungin loading dose of 70 mg and a maintenance dose of 50 mg/day. The median duration of therapy was 10 days. Caspofungin C(24) in SICU patients varied more than those determined for healthy subjects reported in previous studies (0.52-4.08 microg/mL versus 1.12-1.78 microg/mL). According to our model, caspofungin C(24) were predicted to be significantly higher in patients with body weight <75 kg (P=0.019) and patients with albumin concentration >23.6 g/L (P=0.030). CONCLUSIONS: Our results show that body weight and albumin concentration influence caspofungin C(24) in SICU patients and should therefore be considered prognostic factors.


Asunto(s)
Antifúngicos/farmacocinética , Aspergilosis/tratamiento farmacológico , Candidiasis/tratamiento farmacológico , Unidades de Cuidados Intensivos , Péptidos Cíclicos/farmacocinética , Procedimientos Quirúrgicos Operativos , Adulto , Anciano , Antifúngicos/administración & dosificación , Antifúngicos/sangre , Antifúngicos/uso terapéutico , Aspergilosis/microbiología , Peso Corporal , Candida albicans/efectos de los fármacos , Candida glabrata/efectos de los fármacos , Candidiasis/microbiología , Caspofungina , Enfermedad Crítica/terapia , Equinocandinas , Femenino , Humanos , Lipopéptidos , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Péptidos Cíclicos/administración & dosificación , Péptidos Cíclicos/sangre , Péptidos Cíclicos/uso terapéutico , Pronóstico , Albúmina Sérica/análisis
3.
Chemosphere ; 54(8): 1217-24, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14664851

RESUMEN

Analyses of triolein-containing semipermeable membrane devices (SPMDs) have sometimes been impeded by interferences caused by impurities endemic to triolein that codialyze with the analytes. Oleic acid and methyl oleate have been the most troublesome of these impurities because of their relatively high concentrations in triolein and because significant residues of both can persist even after size exclusion chromatographic (SEC) fractionation. These residues have also been blamed for false-positive signals during bioindicator testing of SPMD dialysates. To prevent these problems, a simple, cost-effective procedure was developed for purifying triolein destined for use in SPMDs: the bulk triolein is repeatedly (6x) partitioned against methanol. Tests of the procedure show that 14C-oleic acid is completely removed from the triolein. After SEC fractionation, dialysates of standard-size SPMDs made with the purified triolein contain less than 5 microg of methyl oleate as compared to sometimes more than 500 microg for dialysates (also after SEC) of SPMDs made with unpurified triolein. Gas chromatographic analyses with flame ionization and electron capture detection show that the purification treatment also greatly reduces the number and size of peaks caused by unidentified contaminants in the triolein. Microtox basic assay of dialysates of SPMDs shows that those made with the purified triolein have lower acute toxicities than dialysates of SPMDs made with unpurified triolein. Yeast estrogen screen (YES) testing of SPMDs fabricated with unpurified and purified triolein demonstrates that the purification process removes all background estrogenic activity.


Asunto(s)
Monitoreo del Ambiente/métodos , Membranas Artificiales , Trioleína/aislamiento & purificación , Bioensayo/métodos , Cromatografía en Gel , Diálisis , Monitoreo del Ambiente/instrumentación , Estrógenos no Esteroides/farmacología , Ácido Oléico/química , Ácido Oléico/aislamiento & purificación , Permeabilidad , Pruebas de Toxicidad/métodos , Trioleína/farmacología , Trioleína/toxicidad , Levaduras/efectos de los fármacos , Levaduras/crecimiento & desarrollo
4.
Chemosphere ; 54(6): 695-705, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14602102

RESUMEN

As an integral part of our continuing research in environmental quality assessment approaches, we have developed a variety of passive integrative sampling devices widely applicable for use in defining the presence and potential impacts of a broad array of contaminants. The semipermeable membrane device has gained widespread use for sampling hydrophobic chemicals from water and air, the polar organic chemical integrative sampler is applicable for sequestering waterborne hydrophilic organic chemicals, the stabilized liquid membrane device is used to integratively sample waterborne ionic metals, and the passive integrative mercury sampler is applicable for sampling vapor phase or dissolved neutral mercury species. This suite of integrative samplers forms the basis for a new passive sampling approach for assessing the presence and potential toxicological significance of a broad spectrum of environmental contaminants. In a proof-of-concept study, three of our four passive integrative samplers were used to assess the presence of a wide variety of contaminants in the waters of a constructed wetland, and to determine the effectiveness of the constructed wetland in removing contaminants. The wetland is used for final polishing of secondary-treatment municipal wastewater and the effluent is used as a source of water for a state wildlife area. Numerous contaminants, including organochlorine pesticides, polycyclic aromatic hydrocarbons, organophosphate pesticides, and pharmaceutical chemicals (e.g., ibuprofen, oxindole, etc.) were detected in the wastewater. Herein we summarize the results of the analysis of the field-deployed samplers and demonstrate the utility of this holistic approach.


Asunto(s)
Monitoreo del Ambiente/instrumentación , Manejo de Especímenes/instrumentación , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua/normas , Missouri , Control de Calidad
5.
Toxicol In Vitro ; 18(1): 129-38, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14630071

RESUMEN

In the present study, the yeast estrogen screen (YES) was used to estimate the estrogenic potential of solid phase-extracted water samples from the effluents of two municipal sewage treatment plants (STPs 1 + 2) and from four lanes (left to right) of the river Rhine at Worms, Germany, i.e. downstream the STPs. Estrogenic activities of extracted water samples were expressed as 17beta-estradiol equivalents (E(2)-EQs). Estrogenic activity was detected in the effluents of both STPs with values of 0.242 +/- 0.038 nM (65.96 +/- 10.4 ng/l) and 0.125 +/- 0.026 nM E(2)-EQs (34.1 +/- 7.18 ng/l) at STP 1 and 2, respectively. In river Rhine water, estrogenic activity was lower, however, displaying significant differences between the left and right bank of the river (0.044 +/- 0.003 nM E(2)-EQs [11.97 +/- 0.7 ng/l] for lanes 1-3; 0.071 +/- 0.01 nM E(2)-EQs [19.42 +/- 2.8 ng/l] for lane 4). Chemical analysis of corresponding water samples resulted in a potential estrogenic response in the YES, expressed as E(2)-EQs for the known estrogens and phytoestrogens in the STP effluents with values up to 0.0662 nM E(2)-EQs (18.04 ng/l). In Rhine water from lane 4, however, total estrogenic activity of steroidal estrogens was equal to 0.014 nM E(2)-EQs (3.8 ng/l). Furthermore, total concentrations of flavonoids, fecal- and phytosteroids and resorcyclic lactones were about 1.2 microg/l at STP 1, 0.62 microg/l at STP 2 and 0.25 microg/l at the river Rhine, lane 4. Results indicate that estrogenic activity can clearly be measured in SPT effluents as well as in river Rhine water using the YES in combination with chemical analysis. Results from the bioassay, however, indicated a higher estrogenic potential (expressed as E(2)-EQs) than that obtained by chemical analysis.


Asunto(s)
Monitoreo del Ambiente/métodos , Estrógenos/análisis , Ríos/química , Aguas del Alcantarillado/análisis , Contaminantes Químicos del Agua/análisis , Levaduras/química , Estradiol/agonistas , Estradiol/análisis , Estradiol/fisiología , Estrógenos/química , Estrógenos/farmacología , Heces/química , Flavonoides/análisis , Alemania , Lactonas/análisis , Fitoestrógenos/análisis , Fitoestrógenos/química , Aguas del Alcantarillado/química , Purificación del Agua/métodos , Levaduras/metabolismo
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