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Variety Of Compounds (variety + of_compound)
Selected AbstractsContact dermatitis in Korean dental techniciansCONTACT DERMATITIS, Issue 1 2001Jun Young Lee The high risk of occupational contact dermatitis in dental personnel are well accepted throughout the world. There are few reports concerning occupational skin disease in dental personnel in Korea. The purposes of this study were to investigate the frequency, characteristics and causative factors of contact dermatitis in Korean dental technicians. Recording of personal history, physical examination and patch tests with the Korean standard series and dental screening series were performed in 49 dental technicians. Most of the subjects were exposed to a variety of compounds, including acrylics, metals, plaster, alginate, etc. 22 (44.9%) subjects had contact dermatitis, present or past, and the site involved was the hand in all 22. The most common clinical feature of hand dermatitis was itching (77.3%); scaling, fissuring and erythema were other common clinical features. Metals, including potassium dichromate (24.5%), nickel sulfate (18.4%), mercury ammonium chloride (16.3%), cobalt chloride (12.2%) and palladium chloride (10.2%), showed high positive rates in patch test results of 49 dental technicians. 7 positive reactions to the various acrylics were found in 3 subjects. In our study, the frequency and clinical features of the contact dermatitis showed a similarity to other reports, though the patch test results were somewhat different; a higher patch-positive reaction to metals and a relatively lower patch-positive reaction to acrylics than the patch test results reported in Europe. [source] Characterization of putative ligands for a fish gonadal androgen receptor in a pulp mill effluentENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2006D. G. Joakim Larsson Abstract Fish exposed to pulp and paper mill effluents often become masculinized. A plausible hypothesisis that this is caused by activation of androgen receptors. The present study aimed to investigate if ligands for the fish gonadal androgen receptor (AR2) are present in pulp mill effluent and to characterize/identify these compounds. Extracts of both primary and biologically treated effluents from a Swedish kraft pulp mill were fractionated chemically. Fractions were tested in competitive binding assays for AR2 from ovaries of the Atlantic croaker (Micropogonias undulatus). Primary effluent contained 96 ng dihydrotestosterone equivalents/L, whereas biologically treated effluent was 16 times less potent. Further fractionations and assays of binding activities were performed on the primary effluent. Eight final fractions displaced androgen in the binding assay, and gas chromatography/mass spectrometry (GC/MS) analyses revealed that these contained 37 detectable compounds that were not present in inactive fractions. The majority were moderately polar compounds between 200 and 400 g/mol with hydroxyl/carbonyl groups. Two compounds were ruled out because of their lack of binding to AR2. The mass spectra of a third compound matched that of 4-hydroxy-3 (2-(4-hydroxy-3methoxophenyl)ethyl)-5-metoxyacetophenon, but the remaining candidates could not be fully identified. A search for 21 known steroidal AR2 ligands showed that progesterone, a relatively strong AR2 ligand, was present in the primary effluent (1.6 ,g/L) but was removed during the biological treatment step. The detection of multiple fractions with significant binding activity indicates that a variety of compounds in effluents have the potential to masculinize fish near pulp mills via an androgen receptor-mediated mechanism. [source] Odour-active compounds of Jinhua hamFLAVOUR AND FRAGRANCE JOURNAL, Issue 1 2008Huanlu Song Abstract Using DHS, SAFE, GC,O and GC,MS, the odour-active compounds of Jinhua ham were identified and ranked according their odour potencies. For DHS, the ham powder was purged with a nitrogen stream at a flow rate of 50 ml/min for 25 min, 5 min and 1 min, respectively. The effluent of sample headspace was trapped by a Tenax tube, which was placed onto the vessel for GC,O. The most important odorants (FD factor = 125) in Jinhua ham headspace were ethyl 2-methylbutanoate/ethyl 3-methylbutanoate, hexanal, 1-hexen-3-one, 1-octen-3-one, 2-acetyl-1-pyrroline and 2-methoxyphenol, followed by the following odorants (FD factor = 25): 3-methyl butanal, dimethyl trisulphide, 1-nonen-3-one, butanoic acid, phenylacetaldehyde, 3-methylbutanoic acid, 2-methyl(3-methyldithio)furan, , -nonalctone and 4-methylphenol (p -cresol). For SAFE, the ham powder was extracted with diethyl ether, distilled by SAFE and then separated into neutral/basic and acidic fractions. Both fractions were subjected to AEDA. The relatively high-odour impact compounds (Log3FD Factor ,5) of the N/B fraction of SAFE extract of Jinhua ham were 1-octen-one, ethyl 3-methylbutanoate, methional, phenylacetaldehyde, 2-phenylethanol, (E)-4,5-epoxy-(E)-decenal, p -cresol (4-methylphenol); 3-methylbutanal, hexanal, 2-acetyl-1-pyrroline, decanal, (E,Z)-2,6-nonadienal and (E,E)-decadienal. The important odorants of the Ac fraction of SAFE extract of Jinhua ham were butanoic acid, 3-methylbutanoic acid, hexanoic acid, phenylacetic acid and an unknown. It was shown that the aroma of Jinhua ham consisted of a variety of compounds having different odour properties; a single compound could not characterize the aroma of Jinhua ham. Copyright © 2008 John Wiley & Sons, Ltd. [source] Cyclosporin A suppresses replication of hepatitis C virus genome in cultured hepatocytesHEPATOLOGY, Issue 5 2003Koichi Watashi Persistent infection of hepatitis C virus (HCV) is a major cause of liver diseases such as chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. Searching for a substance with anti-HCV potential, we examined the effects of a variety of compounds on HCV replication using a HCV subgenomic replicon cell culture system. Consequently, the immunosuppressant cyclosporin A (CsA) was found to have a suppressive effect on the HCV replicon RNA level and HCV protein expression in these cells. CsA also inhibited multiplication of the HCV genome in a cultured human hepatocyte cell line infected with HCV using HCV-positive plasma. This anti-HCV activity of CsA appeared to be independent of its immunosuppressive function. In conclusion, our results suggest that CsA may represent a new approach for the development of anti-HCV therapy. [source] X-Cell: a novel indexing algorithm for routine tasks and difficult casesJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 2 2003Marcus A. Neumann X-Cell is a novel indexing algorithm that makes explicit use of systematic absences to search for possible indexing solutions from cells with low numbers of calculated reflections to cells with high numbers of reflections. Space groups with the same pattern of systematic absences are grouped together in powder extinction classes, and for a given peak number range an independent search is carried out in each powder extinction class. The method has the advantage that the correct cell is likely to be found before the rapid increase of possible solutions slows down the search significantly. A successive dichotomy approach is used to establish a complete list of all possible indexing solutions. The dichotomy procedure is combined with a search for the zero-point shift of the diffraction pattern, and impurity peaks can be dealt with by allowing for a user-defined portion of unindexed reflections. To rank indexing solutions with varying numbers of unindexed reflections, a new figure of merit is introduced that takes into account the highest level of agreement typically obtained for completely incorrect unit cells. The indexing of long and flat unit cells is facilitated by the possibility to search for rows or zones in reciprocal space first and then to use the lattice parameters of the dominant row or zone in the unit-cell search. The main advantages of X-Cell are robustness and completeness, as demonstrated by a validation study on a variety of compounds. The dominant phase of phase mixtures can be indexed in the presence of up to 50% of impurity peaks if high-quality synchrotron data are available. [source] Methodology and model for performance and cost comparison of innovative treatment technologies at wood preserving sitesREMEDIATION, Issue 1 2001Mark L. Evans Wood preserving facilities have used a variety of compounds, including pentachlorophenol (PCP), creosote, and certain metals, to extend the useful life of wood products. Past operations and waste management practices resulted in soil and water contamination at a portion of the more than 700 wood preserving sites in the United States (EPA, 1997). Many of these sites are currently being addressed under federal, state, or voluntary cleanup programs. The U.S. Environmental Protection Agency (EPA) National Risk Management Research Laboratory (NRMRL) has responded to the need for information aimed at facilitating remediation of wood preserving sites by conducting treatability studies, issuing guidance, and preparing reports. This article presents a practical methodology and computer model for screening the performances and comparing the costs of seven innovative technologies that could be used for the treatment of contaminated soils at user-specified wood preserving sites. The model incorporates a technology screening function and a cost-estimating function developed from literature searches and vendor information solicited for this study. This article also provides background information on the derivation of various assumptions and default values used in the model, common contaminants at wood preserving sites, and recent trends in the cleanup of such sites. © 2001 John Wiley & Sons, Inc. [source] Determination of curcumol in rat plasma by capillary gas chromatography with a hydrogen flame ionization detectorBIOMEDICAL CHROMATOGRAPHY, Issue 4 2010Xiao Zhao Abstract A simple and sensitive capillary gas chromatography with a hydrogen flame ionization detector (GC-FID) method was developed for the determination of curcumol in rat plasma. From a variety of compounds and solvents tested, buagafuran was selected as the internal standard (IS) and acetonitrile was found to be the best protein precipitation agent and solvent for extracting curcumol from plasma and tissues samples. (Buagafuran was used as an internal standard. Curcumol was extracted by a protein precipitation with acetonitrile.) The samples were determined by GC on an HP-5 column (30.0 m × 0.32 mm, 0.25 ,m); inlet volume 2 ,L; split ratio 10 : 1; inlet temperature 250°C; oven temperature 180°C; flow 1.0 mL/·min; FID 250°C; carrier gas N2. The resulting retention times of curcumol and IS were 6.0 and 9.5 min. There was good linearity over the range 0.133,133.3 ,g/mL (r = 0.9999) in plasma samples. The method recoveries were 97.7,102.0% in plasma, and the intra- and inter-day variances (RSD) were less than 15% in all cases. The GC method was applied to develop a pharmacokinetics study in which experimental rats received a single administration of curcumol by intravenous injection. Copyright © 2009 John Wiley & Sons, Ltd. [source] Genetic polymorphisms of glutathione S-transferase T1 (GSTT1) and susceptibility to gastric cancer: a meta-analysisCANCER SCIENCE, Issue 6 2006Mostafa Saadat The association between glutathione S-transferase T1 (GSTT1) polymorphism and gastric cancer risk has been both confirmed and refuted in a number of published studies. Most of these studies were based on small sample sizes. We carried out a meta-analysis of the research published up to August 2005 to obtain more precise estimates of gastric cancer risk associated with GSTT1 polymorphism. In the present study, 16 case-control studies (with a total of 6717 subjects) were eligible for meta-analysis. There was no evidence of heterogeneity between the studies. The GSTT1 null genotype conferred a 1.06-fold increased risk of gastric cancer, which was not significant (95% confidence interval [CI]: 0.94,1.19). However, in the analysis of ethnic groups, we observed distinct differences associated with GSTT1 status. Restricting analyses to ethnic groups, the pooled odd ratios for the GSTT1 genotype were 1.27 in Caucasians (95% CI: 1.03,1.57) and 0.98 in Asians (95% CI: 0.86,1.13). Glutathione S-transferase M1 (GSTM1) and GSTT1 are involved in detoxification of a variety of compounds, some that overlap between enzymes and some that are highly specific. To investigate whether the profile of glutathione S-transferase genotypes was associated with risk of gastric cancer, further analyses combining the GSTT1 and GSTM1 genotypes were also carried out. There was a significant trend in risk associated with zero, one and two putative high-risk genotypes (,2 = 9.326, d.f. = 1, P = 0.0023). Those who had null genotypes of GSTM1 and GSTT1 had an increased gastric cancer risk compared with those who had both active genes (odds ratio = 2.08, 95% CI: 1.42,3.10). (Cancer Sci 2006; 97: 505,509) [source] | |||||||||||||