Stormwater sampling for particulate, colloidal, and dissolved metals was conducted for several storms at six outfalls in Monmouth County, NJ. Samples were initially sequentially filtered through 5 ...μm, 0.45 μm, and 10 kDa filters. Of the heavy metals, Cu and Zn were mostly either dissolved (<
10 kDa) (20–100%) or in the particulate size fractions >
5
μm (0–>
70%). Pb and Cr were associated exclusively with particles >
5 μm in size. Fe, Al, and Si were found mostly in larger size fractions (>
70%), with smaller amounts 0.45–5 μm in size. Preliminary data from a small set of samples passed through coarser filters suggested that metals may actually be largely associated with particles larger than 20 μm. Variable and sometimes large dissolved fractions of Cu and Zn can contribute to erratic metals removal by structural best management practices (e.g., wet ponds, detention basins). The size fractionation of stormwater constituents has implications for the design and performance of stormwater control structures and the aquatic toxicity risks posed by the metals. The results demonstrate the importance of obtaining particle size data when planning stormwater treatment.
Nonsteroidal anti-inflammatory drugs possess antiproliferative activities that can affect cancer cells. The aim of this study was to examine the antiproliferative effects of ibuprofen on the MKN-45 ...cell line. Cells were treated with ibuprofen for 24, 48 or 72 h, and cell proliferation was evaluated by cell counting and (3)H-thymidine incorporation. Using microarray technology, we studied changes in the gene expression profiles over time after ibuprofen treatment. Ibuprofen induced a dose- and time-dependent reduction in cell number without altering cell viability. Genes involved in the 'biological oxidation' and 'G(1)/S checkpoint' pathways were the most significantly represented at 24 h, whereas genes involved in the 'cell cycle' and 'DNA replication' pathways were represented at 48 and 72 h. Genes associated with the 'apoptosis' pathway were also significantly represented at 72 h. Modulation of the expression of p53 and p53-induced genes (CDKN1A/p21 and GADD45), which are involved in the G(1)/S transition, suggested an effect of ibuprofen on cell-cycle progression. Using flow cytometry, we observed an early block in the G(1) phase of the cell cycle after ibuprofen treatment. In addition, P450 family transcripts were upregulated and intracellular reactive oxygen species (ROS) was increased following 12 h of ibuprofen treatment. Ibuprofen induced ROS, which resulted in cellular alterations that promoted a p53-dependent G(1) blockade. These findings suggest that ibuprofen exerts its antiproliferative actions through cell-cycle control and the induction of apoptosis. Both of these mechanisms appear to be independent of ibuprofen's anti-inflammatory effects.
Epidemiological, clinical, and laboratory studies have suggested that ibuprofen, a commonly used nonsteroidal anti-inflammatory drug, inhibits the promotion and proliferation of certain tumors. ...Recently, we demonstrated the antiproliferative effects of ibuprofen on the human gastric cancer cell line MKN-45. However, high doses of ibuprofen were required to elicit these antiproliferative effects in vitro. The present research compared the antiproliferative effects of ibuprofen delivered freely and released by poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) in MKN-45 cells.
MKN-45 human gastric adenocarcinoma cells were treated with ibuprofen-loaded PLGA NPs. The proliferation of MKN-45 cells was then assessed by cell counting. The uptake of NPs was imaged by fluorescence microscopy and flow cytometry. The release of ibuprofen from ibuprofen-loaded PLGA NPs in the cells was evaluated by gas chromatography-mass spectrometry.
Dramatic inhibition of cellular proliferation was observed in cells treated with ibuprofen-loaded PLGA NPs versus those treated with free ibuprofen at the same concentration. The localization of NPs was cytoplasmic. The initiation of ibuprofen release was rapid, commencing within 2 hours, and then increased slowly over time, reaching a maximum concentration at 24 hours. The inhibition of proliferation was confirmed to be due to the intracellular release of ibuprofen from the NPs. Using PLGA NPs as carriers, ibuprofen exerted an antiproliferative activity at concentrations > 100 times less than free ibuprofen, suggesting greater efficiency and less cellular toxicity. In addition, when carried by PLGA NPs, ibuprofen more quickly induced the expression of transcripts involved in proliferation and invasiveness processes.
Ibuprofen exerted an antiproliferative effect on MKN-45 cells at low concentrations. This effect was achieved using PLGA NPs as carriers of low doses of ibuprofen.
In this study we quantify the ability of dynamic cardiovascular parameters measured by the PulseCO™ algorithm of the LiDCO™plus monitor to predict the response to a fluid challenge in post-operative ...patients.
Surgical patients, admitted to the Intensive Care Unit from the operating theatre were monitored with the LiDCO™plus system. A number of static and dynamic cardiovascular measurements were recorded before and after a fluid challenge. Receiver Operator Characteristic (ROC) curve analysis was used to identify the baseline values, with optimum sensitivity and specificity, to predict responsiveness to a fluid challenge.
Thirty-one patients were enrolled, and received protocol-based fluid challenges. Twelve (38%) responded by demonstrating an increase in stroke volume of >15%. Heart rate (HR) and central venous pressure (CVP) were not statistically different between responders and non-responders. Mean arterial pressure (mAP), systolic pressure variation (SPV), pulse pressure variation (PPV) and stroke volume variation (SVV) were statistically different between responders and non-responders. Parameters with a ROC area under the curve (AUC) significantly >0.5 included SPV 0.70 (0.52-0.88) P=0.046, PPV 0.87 (0.76-0.99) P<0.0002 and SVV 0.84 (0.71-0.96) P=0.0005. The best cut-off values (sensitivity and specificity) to predict fluid were SPV >9 mmHg (73%, 76%), PPV >13% (83%, 74%) and SVV >12.5% (75%, 83%). ROC analysis did not show the AUC to be significantly >0.5 for HR, mAP and CVP CONCLUSION: Dynamic indices measured by PulseCO™ (LiDCO) have a high sensitivity and specificity in predicting fluid responsiveness in sedated and mechanically ventilated patients. A cut-off value for PPV of 13% is the most sensitive and specific indicator of fluid responsiveness.
A 16-year study of a hydrocarbon plume shows that the extent of contaminant migration and compound-specific behavior have changed as redox reactions, most notably iron reduction, have progressed over ...time. Concentration changes at a small scale, determined from analysis of pore-water samples drained from aquifer cores, are compared with concentration changes at the plume scale, determined from analysis of water samples from an observation well network. The small-scale data show clearly that the hydrocarbon plume is growing slowly as sediment iron oxides are depleted. Contaminants, such as
ortho-xylene that appeared not to be moving downgradient from the oil on the basis of observation well data, are migrating in thin layers as the aquifer evolves to methanogenic conditions. However, the plume-scale observation well data show that the downgradient extent of the Fe
2+ and BTEX plume did not change between 1992 and 1995. Instead, depletion of the unstable Fe (III) oxides near the subsurface crude-oil source has caused the maximum dissolved iron concentration zone within the plume to spread at a rate of approximately 3 m/year. The zone of maximum concentrations of benzene, toluene, ethylbenzene and xylene (BTEX) has also spread within the anoxic plume. In monitoring the remediation of hydrocarbon-contaminated ground water by natural attenuation, subtle concentration changes in observation well data from the anoxic zone may be diagnostic of depletion of the intrinsic electron-accepting capacity of the aquifer. Recognition of these subtle patterns may allow early prediction of growth of the hydrocarbon plume.
The neutron magnetic form factor
G
mn
has been determined via a measurement of the ratio of cross sections
D(
e,
e′
n) and
D(
e,
e′
p). The absolute detection efficiency of the neutron detector was ...measured with high accuracy using tagged neutrons produced from
H(
n,
p)
n elastic scattering by means of a high intensity neutron beam. This approach minimizes the model dependence and improves upon the weakest points of previous experiments. Data in the range
q
2=0.2–0.8 (GeV/c)
2 with uncertainties of <2% are presented.
A multidisciplinary study of a crude-oil contaminated aquifer shows that the distribution of microbial physiologic types is strongly controlled by the aquifer properties and crude oil location. The ...microbial populations of four physiologic types were analyzed together with permeability, pore-water chemistry, nonaqueous oil content, and extractable sediment iron. Microbial data from three vertical profiles through the anaerobic portion of the contaminated aquifer clearly show areas that have progressed from iron-reduction to methanogenesis. These locations contain lower numbers of iron reducers, and increased numbers of fermenters with detectable methanogens. Methanogenic conditions exist both in the area contaminated by nonaqueous oil and also below the oil where high hydrocarbon concentrations correspond to local increases in aquifer permeability. The results indicate that high contaminant flux either from local dissolution or by advective transport plays a key role in determining which areas first become methanogenic. Other factors besides flux that are important include the sediment Fe(II) content and proximity to the water table. In locations near a seasonally oscillating water table, methanogenic conditions exist only below the lowest typical water table elevation. During 20 years since the oil spill occurred, a laterally continuous methanogenic zone has developed along a narrow horizon extending from the source area to 50–60 m downgradient. A companion paper J. Contam. Hydrol. 53, 369–386 documents how the growth of the methanogenic zone results in expansion of the aquifer volume contaminated with the highest concentrations of benzene, toluene, ethylbenzene, and xylenes.
Sediments sampled at a hydrocarbon-contaminated, glacial-outwash, sandy aquifer near Bemidji, Minnesota, were analyzed for sediment-associated Fe with several techniques. Extraction with 0.5 M HCl ...dissolved poorly crystalline Fe oxides and small amounts of Fe in crystalline Fe oxides, and extracted Fe from phyllosilicates. Use of Ti-citrate-EDTA-bicarbonate results in more complete removal of crystalline Fe oxides. The average HCl-extractable Fe(III) concentration in the sediments closest to the crude-oil contamination (16.2 μmol/g) has been reduced by up to 30% from background values (23.8 μmol/g) as a result of Fe(III) reduction in contaminated anoxic groundwater. Iron(II) concentrations are elevated in sediments within an anoxic plume in the aquifer. Iron(II) values under the oil body (19.2 μmol/g) are as much as 4 times those in the background sediments (4.6 μmol/g), indicating incorporation of reduced Fe in the contaminated sediments. A 70% increase in total extractable Fe at the anoxic/oxic transition zone indicates reoxidation and precipitation of Fe mobilized from sediment in the anoxic plume. Scanning electron microscopy detected authigenic ferroan calcite in the anoxic sediments and confirmed abundant Fe(III) oxyhydroxides at the anoxic/oxic boundary. The redox biogeochemistry of Fe in this system is coupled to contaminant degradation and is important in predicting processes of hydrocarbon degradation.
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