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This study investigated the composition and leaching characteristics of municipal solid waste incinerator (MSWI) ash and slag. The modified slags were characterized after the melting of MSWI ash mixtures at 1400 degrees C for 30 min. The ash mixtures were composed of different types of MSWI ash, including cyclone ash, scrubber ash and bottom ash, in various proportions. The results indicate that the Cd leaching concentration of the cyclone ash and the Pb leaching concentration of the scrubber ash reached 1.82 and 8.7 mg/L, respectively, which exceeds the ROC EPA's current regulatory thresholds, and can thus be classified as hazardous. The results of the analysis of the metal content and the leaching behavior of heavy metals, showed high concentrations of Cu and Zn, but a low leaching ratio of these metals. Concerning the characteristics of the modified slags, the X-ray diffraction patterns of the MSWI fly ash slag showed that it contained large amounts of glass. The toxicity characteristic leaching procedure (TCLP) leaching concentrations of the target metals of all the slags, met the ROC EPA's regulatory thresholds. The leaching concentrations of heavy metals in the F- and B1-slag were lower than those in the cyclone and the bottom ash, because there was a high amount of SiO(2), which formed a net-like structure in the bottom ash.

We have previously shown that leptospiral membrane lipoprotein preparation (LMLP) extracted from pathogenic Leptospira santarosai serovar Shermani stimulates the secretion of pro-inflammatory mediators in renal tubule epithelial cells, and implicated its role in the initiation of tubulointerstitial nephritis. Renal tubulointerstitial injury is characterized by inflammatory cell infiltrate; however, the stimuli for leukocyte recruitment are not fully understood. Initial studies by cytokine protein array analysis revealed significant upregulation of neutrophil-chemoattractant keratinocyte-derived chemokine (CXCL1/KC) at nanogram range of LMLP stimulation in cultured murine proximal tubule cells (PTCs). As PTCs express Toll-like receptors (TLRs), this study investigated the roles of TLR signaling pathways in PTCs stimulated by LMLP and its relation to CXCL1/KC secretion. The LMLP stimulated the early secretion of CXCL1/KC and enhanced the level of TLR2 mRNA expression in PTCs through time- and dose-dependent effect. The LMLP-stimulated secretion of human growth-related oncogene alpha, a functional homolog to murine KC, in TLR-defective human embryonic kidney 293 cells transiently transfected with TLR2-expressing plasmids and the response was augmented by coexpression of TLR1 and TLR2. Moreover, silencing of TLR2, myeloid differentiation factor 88, and TNF receptor-associated factor 6 with specific small interfering RNA significantly reduces the response caused by LMLP in PTCs. The LMLP-stimulated CXCL1/KC secretion was also significantly reduced by pre-incubating PTCs with a specific p38 inhibitor. These results indicate that LMLP stimulates the production of CXCL1/KC to recruit polymorphonuclear neutrophils at the site of inflammation through a TLR2-mediated pathway in renal tubule cells.

Tubulointerstitial nephritis is a cardinal renal manifestation in leptospirosis and LipL32, the major lipoprotein component of leptospiral outer membrane proteins (OMPs), induces a robust inflammatory response in cultured renal proximal tubule cells through a nuclear factor-kappaB-related pathway. Here, we investigated whether Toll-like receptor (TLR), known to play a pivotal role in innate immunity, could mediate the inflammatory response induced by leptospiral OMPs in renal proximal tubule cells. TLR expression was analyzed by flow cytometry and indirect immunofluorescence in cultured mouse proximal tubule (pyruvate kinase simian virus 40-proximal straight (PKSV-PR)) cells. Reverse transcription-competitive polymerase chain reaction and enzyme-linked immunosorbent assay were undertaken to analyze the inducible effects of inducible nitric oxide synthase (iNOS) and monocyte chemoattractant protein-1 (MCP-1 also termed CCL2) by pathogenic and non-pathogenic leptospiral OMPs and recombinant lipoproteins in either PKSV-PR cells or TLR-transfected human embryonic kidney (HEK) 293 cells. Anti-TLR antibodies were used for blocking experiments. Leptospira santarosai serovar Shermani OMPs and LipL32 induced a significant increase in TLR2 but not TLR4 expression in PKSV-PR cells. The increase in iNOS and CCL2/MCP-1 mRNA expressions could be prevented by an anti-TLR2 antibody, but not by an anti-TLR4 antibody. Furthermore, leptospiral OMPs stimulated both CCL2/MCP-1 mRNA and secreted protein in transfected HEK 293 cells with a TLR2-expressing plasmid, but had no effect in cells with a TLR4-expressing plasmid. In conclusion, these findings indicate that the stimulation of iNOS and CCL2/MCP-1 caused by pathogenic leptospiral OMPs, in particular LipL32, in proximal tubule cells requires TLR2 for the early inflammatory response.

Determination of aniline and 2-chloroaniline in polymer industrial wastewater was examined using high-performance liquid chromatography with on-line microdialysis. After dilution, aniline and 2-chloroaniline in the sample were diffused through a cellular dialysis membrane into the perfusion stream under controlled conditions. Conditions for obtaining optimum dialysis efficiency such as flow-rate and polarity modifier in the perfusion stream, pH and added salt in the sample solution, as well as chromatographic conditions were investigated. The results indicate that the dialysis achieved at a sample matrix pH value of 9.5 with 0.1 M NaCl addition, and the perfusate at 10-microl/min flow-rate offered optimum dialysis efficiency. The aniline and 2-chloroaniline were well separated in an acceptable time on a reversed-phase C18 column eluted with 40% aqueous methanol solution at pH 7.0 and 1.0 ml/min flow-rate. The proposed method provided a very simple procedure to determine aniline and 2-chloroaniline in wastewater. Application was illustrated by the analysis of aniline and 2-chloroaniline in wastewater released from a polymer factory.

Laboratory investigations of nuclear magnetic resonance (NMR) relaxation properties of methane gas in bulk and in porous media are reported. Measurements were performed for methane alone and together with water in glass bead packs and Bentheimer sandstone. Results indicate that surface relaxation effects can be significant and that diffusion effects dominate observed T2 relaxation.

Nuclear magnetic resonance (NMR) relaxation curves for both T1 and T2 on two brine-saturated core plugs have been measured at 1 MHz. T2 distributions were extracted from Carr-Purcell-Meiboom-Gill (CPMG) measurements using different wait times between consecutive echo sequences. The analysis was performed with both a limited number of exponentials and a continuous B-spline basis. The distributions depend strongly on wait time. The distributions were generally restored to the true distributions when a wait time correction was applied.

Four new khellactone esters, (-)-trans-3'-acetyl-4'-senecioylkhellactone, (+-)-cis-3'-acetyl-4'-tigloylkhellactone, (+-)-cis-4-tigloylkhellactone, (+)-trans-4'-tigloylkhellactone, together with 14 known coumarins, isoimperatorin, psoralen, bergapten, xanthotoxol, cnidilin, (-)-selinidin, (-)-deltoin, (+)-pteryxin, (+)-peucedanocoumarin III, xanthotoxin, imperatorin, (+)-marmesin, (+)-oxypeucedanin hydrate, (+)-peucedanol and three chromones, eugenin, (-)-hamaudol, (+)-visamminol, have been isolated from the root of Formosan Peucedanum japonicum. The structures of the new compounds were elucidated by spectral data. The identities of (+)-trans-3'-tigloyl-4'-acetylkhellactone, formerly reported as a new compound, and (+)-cis-3'-angeloyl-4'-acetyl-khellactone, with the known (+)-peucedanocoumarin III and (+)-pteryxin, respectively, are discussed. Among the isolates, seven compounds, eugenin, (-)-selinidin, (+)-pteryxin, imperatorin, bergapten, cnidilin and (+)-visamminol, show strong antiplatelet aggregation activity in vitro.

The use of agarose gel reference standards for quantifying petrophysical properties in porous media is described. The specific interest is to determine the values of fluid saturations and porosity in oil bearing rocks; the MRI methodology for estimating these properties is discussed. It is shown that the relaxation times of the gel reference standard and the relaxation times of the fluid contained in the porous media affect the estimation process. The determination of porosity and fluid saturations can be greatly simplified if the relaxation times of the reference standard and the relaxation times of the fluid are closely matched. Gel concentration of paramagnetic impurities in the form of copper ions is used to control the longitudinal relaxation properties. The relaxation properties of agarose gels, as a function of agarose and paramagnetic impurity concentrations, have been measured at 2.0 T. The data are well fitted by a simple polynomial in agarose concentration and paramagnetic impurity concentration. Finally, a one-dimensional imaging example of use of agarose gels as reference phantoms is discussed.

The mean residue ellipticity, [theta], at any wavelength, lambda, of a protein in aqueous solution is expressed as [theta]lambda = fH[theta]H infinity(1-k/n) + f beta[theta]beta + ft[theta]t + fR[theta]R with two constraints: 1 > or = fj > or = 0 and sigma fj = 1. The subscripts H, beta, t, and R refer to the helix, beta-form, beta-turn, and unordered form. The fractions, fj's, of 15 proteins are based on X-ray crystallography, ft refers to the net beta-turn after cancelling those residues having dihedral angles of opposite sign. The [theta]H infinity of an infinite helix and its chain-length dependence factor, k, were computed from the myoglobin data (Chen et al., 1974, Biochemistry 13, 3350). The average number of residues per helical segment, n, for 15 proteins was about 10, which can be used for proteins of unknown structure. The reference spectra of other three structural elements are computed by a least-squares method. Once the reference spectra are chosen, the same equation above can be used to estimate the fractions of the secondary structure of a protein from its CD data points between 190 and 240 nm at 1-nm intervals. The computed helical content is usually good to excellent (concanavalin A is a notable exception). Inclusion of the beta-turn in the analysis improves the correlation for the estimates of the beta-form, but the computed beta t values are not significantly correlated with the X-ray results. Matrix formulation proves the equivalence of the least-squares method and the integral curve-fitting.

Gentamicin and amikacin, administered in therapeutic doses to normal healthy adults, caused a transient decrease in chemotactic migration of their PMNs. In contrast, RM of leukocytes obtained from these individuals was increased significantly. The magnitude of these changes did not correlate with the serum antibiotic concentrations. Separate in vitro experiments with gentamicin, however, revealed an inverse dose-response relationship with chemotactic suppression. The mechanism(s) involved in modifications of these leukocyte functions is not well understood. These findings may be of clinical significance in patients, especially those with altered host defense mechanisms, who require therapy with these aminoglycoside antimicrobial agents.