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Single Reaction (single + reaction)
Selected AbstractsSNPlexing the human Y-chromosome: A single-assay system for major haplogroup screeningELECTROPHORESIS, Issue 18 2007Gemma Berniell-Lee Abstract SNPs are one of the main sources of DNA variation among humans. Their unique properties make them useful polymorphic markers for a wide range of fields, such as medicine, forensics, and population genetics. Although several high-throughput techniques have been (and are being) developed for the vast typing of SNPs in the medical context, population genetic studies involve the typing of few and select SNPs for targeted research. This results in SNPs having to be typed in multiple reactions, consuming large amounts of time and of DNA. In order to improve the current situation in the area of human Y-chromosome diversity studies, we decided to employ a system based on a multiplex oligo ligation assay/PCR (OLA/PCR) followed by CE to create a Y multiplex capable of distinguishing, in a single reaction, all the major haplogroups and as many subhaplogroups on the Y-chromosome phylogeny as possible. Our efforts resulted in the creation of a robust and accurate 35plex (35 SNPs in a single reaction) that when tested on 165 human DNA samples from different geographic areas, proved capable of assigning samples to their corresponding haplogroup. [source] Large-Scale Synthesis of Water Dispersible Ceria Nanocrystals by a Simple Sol,Gel Process and Their Use as a Chemical Mechanical Planarization SlurryEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 6 2008Taekyung Yu Abstract Ceria nanocrystals with a cube shape were synthesized from the hydrolytic sol,gel reaction of cerium salt in the presence of oleylamine. The overall synthetic process is very simple and readily applicable to the large-scale synthesis of tens of grams of product in a single reaction in air. These ceria nanocrystals are readily dispersible in aqueous media without the addition of any extra dispersing agent. The aqueous dispersion of the ceria nanocrystals was successfully used as a chemical mechanical polishing slurry, and it exhibited high removal selectivity between silicon oxide and silicon nitride at pH 7.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Epigenetic detection of human chromosome 14 uniparental disomy,HUMAN MUTATION, Issue 1 2003S.K. Murphy Abstract The recent demonstration of genomic imprinting of DLK1 and MEG3 on human chromosome 14q32 indicates that these genes might contribute to the discordant phenotypes associated with uniparental disomy (UPD) of chromosome 14. Regulation of imprinted expression of DLK1 and MEG3 involves a differentially methylated region (DMR) that encompasses the MEG3 promoter. We exploited the normal differential methylation of the DLK1/MEG3 region to develop a rapid diagnostic PCR assay based upon an individual's epigenetic profile. We used methylation-specific multiplex PCR in a retrospective analysis to amplify divergent lengths of the methylated and unmethylated MEG3 DMR in a single reaction and accurately identified normal, maternal UPD14, and paternal UPD14 in bisulfite converted DNA samples. This approach, which is based solely on differential epigenetic profiles, may be generally applicable for rapidly and economically screening for other imprinting defects associated with uniparental disomy, determining loss of heterozygosity of imprinted tumor suppressor genes, and identifying gene-specific hypermethylation events associated with neoplastic progression. Hum Mutat 22:92,97, 2003. © 2003 Wiley-Liss, Inc. [source] Some methodological problems concerning nonisothermal kinetic analysis of heterogeneous solid,gas reactionsINTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 10 2001P. Budrugeac Isoconversional methods, those using only one curve , = ,(T) (, is the conversion degree and T is the temperature), and invariant kinetic parameter method were applied to estimate the kinetic parameters from the following nonisothermal data: (1) simulated TG curves for a single reaction; (2) TG curves for thermal degradation of PVC; and (3) TG curves for the dehydration of CaC2O4·H2O. The results obtained by applying various methods for the same system are compared and discussed. Finally, a procedure of kinetic analysis is suggested. Its application could lead to kinetic parameter values that can be used to predict either , = ,(t) curves for other heating rates or , = ,(T) curves for isothermal conditions. © 2001 John Wiley & Sons, Inc. Int J chem Kinet 33: 564,573, 2001 [source] Multienzyme Profiling of Thermophilic Microorganisms with a Substrate Cocktail AssayADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 7-8 2005Renaud Sicard Abstract Labeled substrates for 16 different catalytic activities were combined into a cocktail reagent for multienzyme functional profiling, called PHENOZYMTM. The assay involves a single reaction followed by determination of substrate consumption by HPLC-analysis. The method allows a rapid identification of multiple enzyme activities, and is compatible with a diversity of growth media and reaction conditions (pH, temperature). The PHENOZYMTM cocktail was used to analyze the activity of 16 enzyme activities in a series of microbial strains, including thermophilic microorganisms. The functional profiles were used for a functional classification of the different microbial strains tested by hierarchical cluster analysis. The resulting "phylo-enzymatic" tree revealed associations consistent with the known phylogenetic classification of the strains. The influence of the culture medium on the enzyme activity profiles was also apparent. [source] Optimal design of interconnected bioreactors: New resultsAICHE JOURNAL, Issue 6 2003Jérôme Harmand The optimal design of two interconnected continuous stirred bioreactors in which a single reaction occurs is presented. The term "optimal" should be understood here as the minimum of the total volume of the reactors required to perform a given conversion rate, given a quantity of matter to be converted per time unit. In determining the optimal volume, it is assumed that the input flow may be distributed among the tanks and also that a recirculation loop can be used. The analysis of the optimal configurations is investigated, and the concept of "steady-state equivalent biological system" is highlighted. The class of growth functions for which the results of this study hold is quite wide and includes, in particular, Monod, Haldane, and Aiba kinetics. [source] Amplified fragment length polymorphism analysis in diploid cultivars of rhodesgrassPLANT BREEDING, Issue 1 2001B. E. Ubi Abstract The amplified fragment length polymorphism (AFLP) technique was applied to detect genetic variation in a sample of 47 plants representing 12 diploid cultivars of rhodesgrass. In this analysis, 50±91 easily scorable fragments could be detected in a single reaction. Each of the individual plants was uniquely identified by a combination of three primer pairs and an 80.2% level of polymorphism was obtained. Large amounts of genetic variation were present within all the cultivars. The results showed that AFLPs could be a robust technique for genome analysis in rhodesgrass with a promising potential as a breeding tool. [source] A New Divergent Type of Eukaryotic Methionine Adenosyltransferase is Present in Multiple Distantly Related Secondary Algal LineagesTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 5 2008GABINO F. SANCHEZ-PEREZ ABSTRACT. S -adenosylmethionine is one of the most important metabolites in living cells and is synthesized in a single reaction catalyzed by methionine adenosyltransferase (MAT). At the sequence and structural level, this enzyme is one of the most conserved proteins known. Here we show that some representatives of three distantly related eukaryotic lineages,dinoflagellates, haptophytes, and euglenids,possess a highly divergent type of MAT, which we call MATX. Even though MATX contains all the sites known to be involved in catalysis and the association of monomers, it also has four insertions throughout the protein that are not observed in other MAT homologs. The phylogenetic distribution and affinities of MATX suggest that it originated in a single eukaryotic lineage and was spread via multiple events of eukaryote-to-eukaryote lateral gene transfer. We suggest a tentative model in which the origin of MATX is connected with the progression of secondary endosymbiosis. [source] Formation of Metal Oxide Particles in Atomic Layer Deposition During the Chemisorption of Metal Chlorides: A Review,CHEMICAL VAPOR DEPOSITION, Issue 2 2005L. Puurunen Abstract As has been known for a decade, metal oxide particles can form in a single reaction of gaseous metal chlorides with solid oxides. This is an undesirable effect in the fabrication of thin films by atomic layer deposition (ALD). This work reviews the experimental results related to the metal oxide particle formation and the mechanisms suggested to account for it. The suggested mechanisms cannot explain the observations, but systematic analysis of the possible reaction paths delivers one reaction mechanism candidate, based on a reaction between surface chlorine groups and the hydroxyl groups of gaseous metal hydroxychloride intermediates. The consequences of the proposed mechanism are discussed. [source] An Organocatalytic Asymmetric Tandem Reaction for the Construction of Bicyclic SkeletonsCHEMISTRY - A EUROPEAN JOURNAL, Issue 42 2009Chun-Li Cao Dr. Abstract Cyclic ketones react with (E)-2-nitroallylic acetates in the presence of catalytic pyrrolidine-thiourea, which affords bicyclic skeletons with four or five stereocenters in one single reaction with up to 98,%,ee in moderate to high yields. The cooperative effects of both enamine and the Brønsted acid are found to be crucial for the high reactivity and enantioselectivity of this cascade reaction, which is demonstrated by both theoretical calculation and experimental data. [source] P59 Patch test results to plant extracts and chemicalsCONTACT DERMATITIS, Issue 3 2004Kristiina Alanko Objective and methods:, We review patch test results from two special patch test series for plant allergens, ,plant extracts' and ,allergenic plant chemicals', provided by Prof. Hausen (Germany) and tested in 1992,2003. The standard series contained Sesquiterpene-lactone mix (SL mix) since 1993 (3/1998,10/1999 excluded) and Compositae mix since 3/1998. We present the cases where either SL mix or Compositae mix gave an allergic reaction and where, in addition, the series of plant extracts was tested. Results:, SL mix and Compositae mix were tested to 900 patients. Among them, plant extracts were tested in 122 and plant chemicals in 104 cases. 30 patients had an allergic reaction to Compositae mix and 17 to SL mix as well. In the plant extract series, there were more than 5 allergic reactions to feverfew(21), true chamomile(21), arnica(18), chrysanthemum(18), laurel bay leaf(13), tansy(12), gaillardia(9), yarrow(8) and pot marigold(7). In the plant chemical series, there were 9 allergic reactions to parthenolide and single reactions to primin, chlorophorin and Mansonone A. Conclusions:, Compositae mix gave a positive test reaction always together with SL mix, which gave a positive reaction in only part of these cases. The concentration of Compositae mix was lowered from 6% to 3% in 1/1999 because of cases of active sensitisation. The lower concentration seems to be reliable for detecting allergy, although it still causes active sensitisation. [source] | |||||||||||||