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Trisodium Citrate (trisodium + citrate)
Selected AbstractsInfluence of temperature and time before centrifugation of specimens for routine coagulation testingINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 4 2009G. L. SALVAGNO Summary The accurate standardization of the preanalytical phase is of pivotal importance for achieving reliable results of coagulation tests. Because information on the suitable storage conditions for coagulation testing is controversial, we aimed at investigating the sample stability with regard to the temperature and time before centrifugation. The activated partial thromboplastin time (aPTT), prothrombin time (PT), fibrinogen and D-dimer were assayed in specimens collected from 26 consecutive patients on antivitamin K therapy on the ACL TOP analyzer. Three primary 3.6-ml siliconized evacuated tubes containing 0.109 mol/l buffered trisodium citrate were sequentially collected from each patient. These three tubes were mixed, pooled and divided into seven identical aliquots. The first aliquot was immediately centrifuged according to the standard protocol [1500 g for 15 min at room temperature (RT)] and analyzed. The other aliquots were left for 3, 6 and 24 h, respectively, at RT or 4 °C, and then centrifuged and analyzed. Test results were compared with those obtained on the reference specimen. Statistically significant prolongations were observed for aPTT in all the samples. Such differences exceeded the analytical quality specifications for desirable bias in the samples stored for 24 h. A significant reduction, yet comprised within the desirable bias, was observed for PT and fibrinogen in uncentrifuged specimens stored at RT for 3 and 6 h. No significant biases could be recorded in D-dimer. In conclusion, a 6-h storage of uncentrifuged specimens at either RT or 4 °C may still be suitable to achieve results of routine coagulation testing comprised within the analytical quality specifications for desirable bias. [source] Effects of Ingredients on the Functionality of Fat-free Process Cheese SpreadsJOURNAL OF FOOD SCIENCE, Issue 5 2000B.J. Swenson ABSTRACT Emulsifying salts and hydrocolloids, cook time, cook temperature, and pH were evaluated to characterize their effects on firmness, meltability, and spreadability of fat-free process-cheese spreads. Disodium phosphate and trisodium citrate produced properties closest to those of a full-fat reference cheese, with trisodium citrate providing the most meltability. In all cases, incorporation of hydrocolloids resulted in increased firmness, decreased melt, with varying results on spreadability. Increases in cook time generally produced softer, more meltable cheeses, while increases in cook temperature decreased firmness and increased meltability and spreadability. [source] Cloning, expression, purification and crystallization of a transcriptional regulatory protein (Rv3291c) from Mycobacterium tuberculosis H37RvACTA CRYSTALLOGRAPHICA SECTION D, Issue 10 2004Tripti Shrivastava Rv3291c, the translational product of the Mycobacterium tuberculosisRv3291c gene, is an 18,kDa protein. It is a putative transcriptional regulatory protein belonging to the leucine-responsive regulatory protein/asparagine synthase C (Lrp/AsnC) family, which are proteins that have been identified in archaea and bacteria. Rv3291c probably plays a significant role during the persistent/latent phase of M. tuberculosis, as supported by its up-regulation several-fold during this stage. Orthorhombic crystals of recombinant Rv3291c have been grown from trisodium citrate dihydrate-buffered solutions containing monoammonium dihydrogen phosphate. Diffraction data extending to 2.7,Å have been collected from a single crystal with unit-cell parameters a = 99.6, b = 100.7, c = 100.6,Å. Assuming an octamer in the asymmetric unit results in a Matthews coefficient (VM) of 1.75,Å3,Da,1, corresponding to a solvent content of about 30%. [source] Crystallization and preliminary X-ray crystallographic analysis of nicotinic acid mononucleotide adenylyltransferase from Pseudomonas aeruginosaACTA CRYSTALLOGRAPHICA SECTION D, Issue 5 2004Hye-Lee Kim The enzyme nicotinic acid mononucleotide adenylyltransferase (NaMN AT; EC 2.7.7.18) is essential for the synthesis of nicotinamide adenine dinucleotide and is a potential target for antibiotics. It catalyzes the transfer of an adenyl group from ATP to nicotinic acid mononucleotide to form nicotinic acid adenine dinucleotide. NaMN AT from Pseudomonas aeruginosa was overexpressed in Escherichia coli and crystallized at 291,K using 100,mM bis,Tris propane pH 7.0, 700,mM trisodium citrate and 15%(v/v) glycerol. X-ray diffraction data have been collected to 1.70,Å. The crystals are tetragonal, belonging to space group P4122 (or P4322), with unit-cell parameters a = b = 65.02, c = 109.80,Å. The presence of one monomer in the asymmetric unit gives a reasonable VM of 2.15,Å3,Da,1, with a solvent content of 42.7%. [source] Expression, purification, crystallization and preliminary crystallographic analysis of phosphoserine aminotransferase from Bacillus alcalophilusACTA CRYSTALLOGRAPHICA SECTION D, Issue 12 2003Anatoly P. Dubnovitsky Phosphoserine aminotransferase (PSAT; EC 2.6.1.52) from Bacillus alcalophilus, an obligatory alkalophile with optimum growth at pH 10.6, was overexpressed in Escherichia coli, purified and crystallized under two different conditions using the hanging-drop vapour-diffusion method. Crystals were obtained using trisodium citrate dihydrate or PEG 400 as a precipitating agent. Crystals grown in the presence of trisodium citrate belong to the orthorhombic space group C2221, with unit-cell parameters a = 105.6, b = 136.6, c = 152.0,Å, and those grown in the presence of PEG 400 belong to the orthorhombic space group P21212, with unit-cell parameters a = 143.7, b = 84.3, c = 67.4,Å. Complete data sets were collected to 1.7 and 1.6,Å resolution, respectively, at 100,K using synchrotron radiation. Analysis of the structure of B. alcalophilus PSAT may reveal structural features that contribute to enzyme adaptability at high pH values. [source] | ||||||||||