EDTA Therapy for Vascular Disease
The iron-chelating EDTA-derived reagent (EDTAcyst(NPS) Fig. 1A Note 2) can be synthesized by a simple route from cysteamine, EDTA, tert-butanol and 2-nitrophenylsulfenyl chloride (9). The steps in the synthesis are 3. Link ieri-butyl cysteamine via its amino group to the carboxyl of EDTA in a peptide bond, using a large excess of EDTA to promote reaction of only a single carboxyl molecule (28). 4. Purify the product EDTAcyst(tBu) by C18 reverse-phase HPLC. 6. Purify the product EDTAcyst(NPS) by C18 reverse-phase HPLC.
Chelating agents are used for poisoning with heavy metals. They incorporate the metal ions into an inner ring structure in the molecule (Greek chele, claw) by means of structural groups called ligands (Latin ligare, to bind) effective agents form stable, biologically inert complexes that are excreted in the urine.
Buffer A 50 mM Tris-HCl, pH 7.5 1 mM EDTA, 1 mM dithiotreitol (DTT), 50 mMNaCl. 3. Buffer B 50 mM Tris-HCl, pH 7.5, 1 mM EDTA, 1 mM DTT, 1 M NaCl. 4. Buffer C 50 mM Tris-HCl, pH 7.5, 1 mM EDTA, 1 mM DTT, 250 mM NaCl. 5. Buffer D 50 mM Tris-HCl, pH 7.5, 1 mM EDTA, 1 mM DTT, 500 mM NaCl. 6. Buffer E 50 mM Tris-HCl, pH 7.5, 1 mM EDTA, 5 mM DTT, 250 mM NaCl. 7. Buffer F 50 mM Tris-HCl, pH 7.5, 1 mM EDTA, 5 mM DTT, 250 mM NaCl, 50 (v v) glycerol.
Tetracycline derivatives inhibit both the activity of the MMPs and their production. They can inhibit MMP-1, -3, and -13 (the col-lagenases) and MMP-2 and -9 (the gelatinases) by several different mechanisms. These mechanisms include (1) blocking MMP activity by chelation of zinc at the enzyme active site, (2) inhibiting the proteolyticactivation of the pro-MMP, (3) decreasing the expression of the MMPs, and (4) preventing proteolytic and oxidative degradation of the MMPs.
To each flask add 5 mL of freshly thawed trypsin-EDTA solution at room temperature (20 C) and incubate for 5 min at room temperature with gentle rocking every 30 sec to ensure that the entire surface area of the flask and explants is exposed to the trypsin-EDTA solution. 4. Remove and discard all but 2 mL of the trypsin-EDTA solution, and then incubate the cells for an additional 5 min at 37 C. 5. Remove the flasks from the incubator and examine under the microscope. Look for the presence of rounded, highly refractile cell bodies floating in the trypsin-EDTA solution. If none, or only a few, are visible tap the base of the flask sharply on the bench top in an effort to dislodge the cells. If this is without effect, incubate the cells for a further 5 min at 37 C.
Because of their synthesis and secretion of an extensive collagen-rich extracellular matrix, HBDCs cultured in the continuous presence of ascorbate cannot be subcultured using trypsin-EDTA alone. They can, however, be subcultured if first treated with purified collagenase. The basic procedure is as follows 5. Gently rinse the cell layer twice with 10 mL of Ca2+- and Mg2+-free PBS. To each flask add 5 mL of freshly thawed trypsin-EDTA solution, pH 7.4, at room temperature (20 C).
Preelectrophorese the gel for 4.5 h at 12 V cm. Use 20 mM HEPES, pH 8.0, 1 mM Na-EDTA as running buffer. Change the running buffer and preelectrophorese for another 30 min at 6 V cm with recirculation of the buffer (see Note 9). 5. Add EDTA to 20 mM to stop the digestion and sucrose to 10 (see Note 12). Load the reconstitute on the gel (10 g reconstituted DNA per 2-cm-wide slot). Electrophorese at room temperature for 5-8 h at 6 V cm with recirculation of the buffer at approx 300 mL h.
B. 0.2 M neutralized ethylenediaminetetraacetic acid (EDTA) as a metalloprotease inhibitor dissolve EDTA with deionized water, neutralize with NaOH, and add deionized water to make 0.2 M EDTA. Store at room temperature. 3. Mix 5 ml of 10 x PBS, 5 ml of 0.2 M neutralized EDTA, and 0.5 ml of 0.2 M PMSF-1 M NEM to make 50 ml of PBS-20 mM EDTA-10 mM NEM-2 mM PMSF (PBS-inhibitors).
To data provided by USRDS for 1994 through 1998, glomerulonephritis accounted for 9.1 of ESRD, hypertensive renal disease was present in 25.2 , secondary glomerulonephritis and vasculitis involved 2.2 , 3.6 were unknown etiology and interstitial nephritis pyelonephritis accounted for 3.8 of all cases of ESRD being treated in USA 61 . From EDTA 62 , 24.1 of new ESRD patients in 1987 were due to glomerulonephritis, 16.6 due to pyelonephritis interstitial nephritis, 2.8 due to analgesic and other nephrotoxic agents, 9.9 due to renal vascular disease and 14.4 due to chronic renal failure of unknown etiology for a total of almost 68 . Thus, there exist a substantial number of ESRD patients whose etiology could involve a component of long-term, low level exposure to either environmental or occupational toxicants.
0.2 M NEM in ethanol) 0.2 M neutralized EDTA (Section IV.A) 0.5 ml Stock solutions (the 10 x buffer and the 100 x inhibitor mixture) are stored at 20 C. The final reaction mixture contains 100 mM Tris-HCl, pH 7.5, 30 mM NaOAc, 0.2 mM PMSF, 0.072 mM pepstatin, 2 mM NEM, and 2 mM EDTA in addition to CSPGs and chondroitinase ABC. After the reaction mixture is incubated for 1 h at 37 C, the core protein is precipitated by adding 3 vol. (150 ml) of 95 ethanol-1.3 KOAc.
Proteinase K solution 20 mg mL proteinase K (Sigma-Aldrich, St. Louis, MO) in a 10 mM Tris-HCl buffer (pH 8.0) containing 1 mM EDTA, 0.3 M sodium acetate, and 0.2 (w v) sodium dodecyl sulfate (SDS). Aliquots of this stock solution are stored at -20 C. Proteinase K working solutions are prepared freshly by diluting the proteinase K stock in the same buffer 10-fold to 2 mg mL. 5. TE 1X buffer 10 mM Tris-HCl (pH 8.0) containing 1 mM EDTA. 9. TBE 1X buffer 89 mM Tris base, 89 mM boric acid, and 2 mM EDTA in H2O. 17. HIGH buffer 1 (w v) bovine serum albumin (BSA), 0.2 M sodium phosphate, 15 (w v) formamide, 1 mM EDTA, and 7 (w v) SDS in H2O. 20. Solution 1 15 mM Tris-HCl (pH 7.5) supplemented with 60 mM KCl, 15 mM NaCl, 0.5 mM spermine, 0.15 mM spermidine, 14 mM -mercaptoethanol, 2 mM EDTA, and 0.3 M sucrose (store at 4 C). 21. Solution 2 15 mM Tris-HCl (pH 7.5) supplemented with 60 mM KCl, 15 mM NaCl, 0.5 mM spermine, 0.15 mM spermidine, 14 mM -mercaptoethanol, 1 mM EDTA, and 1.37 M...
Chromatin experiments generally are performed in 10 mM Tris-HCl, 0.25-1.0 mM EDTA (TE) buffer containing various salts and salt concentrations at a desired pH (3,11,14-16). Other nonabsorbing buffers, e.g., HEPES, have also been used (12,13). The buffers can include any component that does not interfere with the chromatin sample absorbance at 260 nm, e.g., 5 glycerol.
5 Sucrose buffer 5 (w v) sucrose, 23 mM KCl, 17 mM NaCl, 0.1 mM EDTA, 2 mM MgCl2, 20 mM HEPES, 1 mM DTT, 10 mg mL phenylmethylsulfonyl fluoride, 2 mg mL leupeptin, 2 mg mL pepstatin, pH 7.5. 3. 20 Sucrose buffer 20 (w v) sucrose, 23 mM KCl, 17 mM NaCl, 0.1 mM EDTA, 2 mM MgCl2, 20 mM HEPES, 1 mM DTT, 10 mg mL phenylmethylsulfonyl fluoride, 2 mg mL leupeptin, 2 mg mL pepstatin, pH 7.5.
After allowing mature osteoclasts to adhere to culture dishes overnight, as described in Subheading 3.1., remove the nonadherent bone marrow cells and pool with cells that have been removed by washing in PBS and pronase-EDTA digestion. Seed these cells into 10-cm diameter petri dishes (3 x 107 cells per 3. After 10 d, remove the stromal layer by washing extensively with PBS. This usually yields 95 pure multinucleated, TRAP-positive osteoclast-like cells (capable of resorbing bone mineral when the marrow cells are cultured on ivory discs) therefore further purification using pronase-EDTA is not usually required.
18 Blake CM, Lazarus CR, Roe D 1997 Long-term precision of glomerular filtration rate measurements using 51Cr-EDTA plasma clearance. Nucl Med Commun 18 776-784 44 Rydstrom M, Ahlmen J, Cederquist I, Tengstrom B 1995 Measurement of glomerular filtration rate by single-injection, single-sample techniques, using 51Cr-EDTA or iohexol. Scand J Urol Nephrol 29 135-139
Running buffer for RNA analysis 0.5X TAE (20 mM Tris-acetate, 0.5 mM EDTA, 0.3 M-g mL ethidium bromide filtered) 1 agarose gel for RNA analysis (gel is run in 0.5X TAE). 4. Reagents for transcription reactions 200 mM dithiothreitol ribonucleotide solution (GTP, ATP, UTP, and CTP each at 5 mM), nuclease-free H2O, 10X transcription buffer (standard buffer 400 mM Tris-HCl, pH 7.5, 100 mM NaCl, 60 mM MgCl2, 20 mM spermidine 6 ), RNase inhibitor, bacteriophage RNA polymerases (e.g., T7or T3) or a commercially available in vitro transcription kit, TE (25 mM Tris-HCl, 10 mM EDTA, pH 8.0).
Cell separating buffer was used throughout the magnetic cell sorting procedure and made as directed by the manufacturer (Miltenyi Biotec Ltd.). PBS, pH 7.2, was supplemented with 0.5 heat-inactivated fetal or neonatal bovine serum and 2 mM ethylenediaminetetraacetic acid (EDTA Sigma Aldrich Ltd.).
Lee and Cowman (61) adapted methods used in the electrophoretic separation of high molecular weight nucleic acids for the separation of high molecular weight hyaluronan. They proposed the use of agarose gel at 0.5 in a continuous Tris-acetate-EDTA buffer for the separation of hyaluronan (Fig. 6). Sample loads of approximately 4-7 mg were required for polydisperse samples and the separated pattern was visualized by staining with the dye Stains-All For hyaluronan standards of known average molecular weight, the electrophoretic mobility was found to be approximately linearly related to the logarithm of the hyaluronan molecular weight over the range of 0.2 X 106 - 6 X 106. Larger molecules may be separable by this method, but no suitable standards have been available. The method was shown to be useable preparatively, but yields are low and some degradation occurs during extraction of the hyaluronan from the gel. Impure hyaluronan samples containing high levels of contaminating protein...
As sources of osteoclast precursors use peripheral blood (obtained from volunteers by venipuncture), cord blood (obtained with the consent of mothers from placentae postpartum, or bone marrow (aspirated from the posterior iliac crest of volunteers under either general or local anesthetic see Note 6). Use heparin or EDTA to prevent coagulation. 2. Dilute the blood and bone marrow 1 1 in PBS. Additional heparin or EDTA is not required.
Select CD14-positive cells by adding 10 L of anti-CD14-FITC to 1 x 107 PBMNCs resuspended in 100 L of cell separating buffer. Cell separating buffer is used throughout the magnetic cell sorting procedure and is made as directed by the manufacturer (Miltenyi Biotec Ltd.). In brief, PBS, pH 7.2, is supplemented with 0.5 heat-inactivated fetal or neonatal bovine serum and 2 mM EDTA (Sigma Aldrich Ltd.). Mix the cells and antibody well using a pipet and then incubate the mixture in the dark for 10 min at 6 C. MiniMACS columns can separate 103-107 labeled cells from a total population of 2 x 108 cells but larger scale selections are possible with different columns.
2X hybridization buffer 1.5 M NaCl, 100 mM HEPES-NaOH, pH 7.0, 2 mM EDTA. 4. 2X proteinase K solution 0.4 mg mL proteinase K, 100 mM Tris-HCl, pH 7.5, 2 SDS, 20 mM EDTA. 6. T1 RNase buffer 10 mM HEPES-NaOH, pH 7.5, 0.2 M NaCl, 1 mM EDTA. 7. Sample loading buffer 80 deionized formamide 89 mM Tris base, 89 mM boric acid, 2 mM EDTA (1X TBE) 0.05 xylene cyanol, 0.05 bromophenol blue. 8. HeLa whole-cell extract (see Note 6) Prepare essentially as initially described (35), although 0.1 mL of 1 MNaOH (not 0.01 mL) is added per 10 g ammonium sulfate to the whole-cell extract suspension. As a final step, dialyze into extract buffer 20 mM HEPES-NaOH, pH 7.9, 100 mM KCl, 12.5 mM MgCl2, 0.1 mM EDTA, 2 mM DTT, 17 glycerol. If it is desired, remove histone H1 from the crude HeLa whole-cell extract by precipitation with 2.26 M ammonium sulfate (7,36), resuspension of the pellet after centrifugation into extract buffer, and dialysis into this same buffer. Protein concentration of the final extract...
Trypsin-EDTA solution PBS(-) containing 0.05 trypsin and 0.5 mM EDTA for detachment of cells from culture plates. 6. Pronase-EDTA solution PBS(-) containing 0.001 pronase and 0.02 EDTA for removal of osteoblasts from cocultures. Pronase is dissolved in PBS(-) containing 0.02 EDTA just before use.
The presence of fibrin strands in serum that is processed for analysis prior to complete clot formation is known to cause errors in many immunoassay systems. The susceptibility of the different automated immunoassay analyzers to such interference varies. Fibrin strands are only of concern for NT-proBNP measurement when conducted using serum samples. Blood for BNP determination must be collected in EDTA-coated plastic tubes. EDTA is important for in vitro stabilization of BNP because it inhibits degradation by metalloproteases (36). NT-proBNP may also be measured using fresh plasma samples. If serum is used, it is important to ensure that the clotting process is complete prior to cen-trifuging the sample in order to eliminate the presence of microfibrin strands. Icteric and hemolyzed samples may also cause inaccuracy in immunoassays based on fluorimetric detection of the signal.
Because the purity of osteoclasts in the crude osteoclast preparation is only 2-3 , further purification is essential for biochemical studies of osteoclasts. Osteoclasts are easily purified from the crude osteoclast preparation placed on plastic dishes by treatment with pronase-EDTA solution (12,13). This procedure is identical to that described in the chapter by Coxon et al. to obtain pure mature rabbit osteoclasts. 2. Adherent cells are washed with a-MEM, and treated with 8 mL of pronase-EDTA solution for 10 min.
DNase I stop buffer 20 mM Tris-Cl, pH 7.5, 50 mM EDTA, 2 SDS, 200 pg mL proteinase K (Sigma), 0.25 mg mL tRNA (Sigma). 12. TBE 0.09 M Tris-borate, 0.002 M EDTA. 15. DSB 3 SDS 50 mM Tris-HCl, pH 8, 0.1 M EDTA, 25 glycerol, 0.05 bromophenol blue and xylene cyanol, 200 pg mL proteinase K (Sigma).
Acidifiers, Cu chelating agents (e.g., high phosphate concentration), Cu2+ reducing agents (e.g., reducing sugars, thiols), Tris, HEPES, EDTA, neutral detergents Acidifiers, Cu chelating, reducing agents, Tris, ammonium sulfate, EDTA, lipids + phospholipids. (Neutral detergents and SDS do not interfere) aTris tris(hydroxymethyl)aminomethane HEPES acid SDS sodium dodecyl sulfate EDTA ethylenediaminetetraacetic acid. aTris tris(hydroxymethyl)aminomethane HEPES acid SDS sodium dodecyl sulfate EDTA ethylenediaminetetraacetic acid.
1X TE buffer 10 mM Tris HCl, pH 8.0 and 1 mM EDTA, pH 8.0. 2. Sorbitol solution 0.9 M sorbitol (Fisher), 0.1 M Tris HCl, pH 8.0, 0.1 M EDTA are prepared with water and filter sterilized using a 0.22- m filter. 5. 10X TBE electrophoresis stock buffer 0.89 M Tris base 0.89 M boric acid 20 mM EDTA, pH 8.0. A 1X working solution is made by diluting 1 10 with water.
Heparinized whole blood is preferred, but EDTA whole blood may also be used. Blood samples must be kept covered, contain no air bubbles, and be well mixed, properly labeled, and maintained in 2 to 4 C (ice water) and analyzed within 4 hours. Clotted blood can be used for forensic purposes but must be homogenized and not exposed to air during processing. Postmortem blood or blood containing denatured hemoglobin can't be used. Syringes with lyophilized heparin are available but must have adequate amount of blood added to maintain the correct blood-to-anticoagulant ratio, and proper mixing is required to prevent clots.
Buffer 1 50 mM Tris-HCl, pH 8.0, 20 (v v) isopropanol (analytical grade or similar quality), 0.1 mM EDTA, 1 mM dithiothreitol. Prepare immediately prior to use. 2. Buffer 2 50 mM Tris-HCl, pH 8.0, 8 M urea (ICN Ultra Pure Urea no. 821527), 0.1 mM EDTA, 1 mM dithiothreitol. Prepare immediately prior to use. 3. Buffer 3 50 mM Tris-HCl, pH 8.0, 0.005 Tween-40 (Sigma), 0.1 mM EDTA, 1 mM dithiothreitol. Prepare immediately prior to use.
Grow HeLa cells in 150-mm tissue-culture dishes so that they are 70-80 confluent the day before screening. Approximately 2 o 109 cells (10-12 150-mm plates) are needed for a 50-plate assay using 384-well plates. Aspirate media and wash cells once with 15 mL PBS. Add 2 mL trypsin-EDTA per plate and incubate plates at 37 C for 2-5 min. Resuspend cells in DMEM to a final concentration of 2 o 105 cells per mL. Add appropriate volume of adenovirus to cell suspension. 1. Grow B-SC-1 cells in 150-mm plates to 70-80 confluence the day before screening. Aspirate media and wash cells once with 15 mL PBS. Add 2 mL trypsin-EDTA per plate and incubate plates at 37 C for 2-5 min. Resuspend cells in DMEM to a final concentration of 2.6 o 105 cells per mL.
No bound microgel particles were eluted with running buffer or with specific eluents, imidazole (up to 0.3 M) or EDTA (up to 50 mM). However, when cryogel with bound microgel particles was compressed in the presence of either eluent, up to 60 of microgel particles was released from the cryogel. As the pulse of the eluent at 20-fold higher flow rate did not succeed in re
Figure 7 Agarose gel electrophoresis of nearly monodisperse hyaluronan standards and commercial hyaluronan. Gel was 0.7 agarose in Tris-acetate-EDTA (minigel format), stained with Stains-All by the method of Lee and Cowman (61). S a mixture of 5 different monodisperse SelectHA preparations with indicated Mw determined by SEC-MALS C and C0 commercial hyaluronan samples D DNA standards, Bioline Hyperladder 1, containing DNA of 10, 8, 6, 5, 4, 3, 2.5, 2, 1.5 kb D0 DNA standards, BioRad 1 Kilobase Ruler, containing DNA of 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2 kb. Figure kindly provided by P DeAngelis and W Jing. Figure 7 Agarose gel electrophoresis of nearly monodisperse hyaluronan standards and commercial hyaluronan. Gel was 0.7 agarose in Tris-acetate-EDTA (minigel format), stained with Stains-All by the method of Lee and Cowman (61). S a mixture of 5 different monodisperse SelectHA preparations with indicated Mw determined by SEC-MALS C and C0 commercial hyaluronan samples D DNA...
TBE 89 mM Trizma Base (Sigma), 89 mM Boric acid, 2 mM EDTA. 9. Prehybridization solution 0.25 M phosphate buffer, pH 7.2, 7 SDS, 1 mM EDTA, pH 8.0, 50 pg mL tRNA. 11. Hybridization solution 0.25 M phosphate buffer, pH 7.2, 7 SDS, 1 mM EDTA, pH 8.0. 12. Washing solution I 40 mM phosphate buffer, pH 7.2, 5 SDS, 1 mM EDTA, pH 8.0 (prewarmed overnight in the 70 C oven). 13. Washing solution II 40 mM phosphate buffer, pH 7.2, 1 SDS, 1 mM EDTA, pH 8.0 (prewarmed overnight in the 70 C oven).
A surprising result was that enhancement of oxidative stress led to further TFs upregulation. We therefore wondered what addition of an antioxidant would do and fortuitously chose PDTC as the antioxidant. Much to our surprise, PDTC produced apoptosis in the melanoma cells, even at very low concentrations. With the realization that PDTC is both an antioxidant and chelator, we tested a series of chelators on melanoma cell growth. Antioxidants had little effect but transition metal chelation produced a strong apoptotic effect. One such compound, disulfiram, was readily available, as it has been used for over 50 years, as an anti-alcohol aversion drug and was found to be active as an antimelanoma therapy at nanomolar concentrations (Cen et al. 2002, 2004). Based on these and other studies, we have now initiated a phase II trial of disulfiran plus arsenical trioxide for patients with advanced melanoma disease.
Purified TRAP-positive osteoclasts formed in cocultures of mouse osteoblasts and bone marrow cells. Primary osteoblasts (2 x 106 cells) and bone marrow cells (2 x 107 cells) were cocultured for 7 d on a collagen gel coated dish. The dish was then treated with 0.2 collagenase solution to recover all the cells from the dish. The cells released from the dish were collected by centrifugation and suspended in 10 mL of a-MEM containing 10 FBS (the crude osteoclast preparation). The crude osteoclast preparation was placed on a 10-cm culture dish for 10 h in the presence of 10 FBS (A). The purity of osteoclasts in this crude preparation was only 2-3 . Adherent cells were washed with a-MEM, then treated for 10 min with 8 mL of pronase-EDTA solution. Osteoblasts were then removed by gentle pipetting. More than 90 of the adherent cells on the dish were TRAP-positive mononuclear and multinucleated cells (B). Scale bar 200 m. Fig. 3. Purified TRAP-positive osteoclasts formed in cocultures...
Cis-trans isomerism around single bonds has been widely used in supramolecular chemistry, in particular with bulky biaryl compounds such as the metal-chelating agents bipyridines and sterically hindered binaphthyl motifs. In these compounds, a moderate barrier to rotation exists due to the resonance of the two con
B. 4 M guanidine-HCl-50 mM Tris-HCl, pH 7.5-20 mM EDTA (Guanidine-HCl-EDTA) Dissolve solid guanidine-HCl in ca.1 2 vol. of deionized water. Add 1 20 vol. of 1 M Tris-HCl, pH 7.5, 1 10 vol. of 0.2 M neutralized EDTA (Section IV.A), and then add deionized water to a guanidine HCl-concentration of 4 M. Store at 4 C. 3. Mix 4 ml of Guanidine-HCl-EDTA and 40 ml of inhibitor mixture (4 M guanidine-HCl solution). The mixed solution should be used immediately since most of the protease inhibitors are unstable in an aqueous solution.
The LOD of 0.2 mol L using indirect detection and phthalic acid is close to the reference limit of 0.4 mol L, the upper limit seen in normal individuals. Because methylmalonic acid rises dramatically (10-100 times normal levels) in vitamin B12 deficiency, the assay is adequate for clinical purposes. Indirect detection, however, depends entirely on migration time for identification. There is always the possibility that a coeluting compound could be hidden in the methylmalonic acid peak, falsely elevating the value. When methylmalonic acid is elevated, dilution should be used to reduce the possibility of interference by coeluting compounds. Also plasma specimens collected with citric acid as the anticoagulant cannot be analyzed with this assay. The massive peak due to citric acid will overwhelm all other peaks in the vicinity, including the one for methylmalonic acid (see Fig. 1). EDTA plasma does not cause a similar problem. Specimen preparation is based on an organic phase extraction,...
Breaking buffer 0.6 M sorbitol, 20 mM potassium phosphate, pH 7.4, 1 mM PMSF, protease inhibitor mix leupeptin (1.25 g mL), antipain (0.75 g mL), chymostatin (0.25 g mL), elastinal (0.25 g mL), pepstatin (5 g mL), phenylmethylsulfonyl fluoride (1 mM), and EDTA (1 mM) (see Note 1).
Saturate all binding sites with excess Fe (ferric ammonium citrate or ferric chloride). Remove excess unbound iron (using ion-exchange resin or chelation by MgCO3, followed by centrifugation and decanting the supernatant containing saturated transferrin). Run as per iron method above.
Assay buffer (AB) 25 mM Tricine-HCl, pH 7.8, 8 mM MgSO4, 0.1 mM EDTA, 33 y,M DTT, 470 M D-luciferin, 240 M coenzyme A, and 0.5 mM ATP. Assay buffers are quick frozen in liquid nitrogen and stored at -70 C as 1.3-mL aliquots in amber-colored tubes. AB is light-sensitive and should be stored in dark.
Rotary shadowing electron microscopy studies have revealed that C6S is capable of forming aggregates of two or more chains (Scott et al., 1992). The charge distribution of the twofold helix of C6S is near the periphery, creating regions of hydrophobicity. Such hydrophobic zones from separate chains can interact with each other. Chondroitin-4-sulfate is incapable of such network formation, as sulfate groups are clustered close to the helical axis, minimizing aggregation behavior. Although C4S cannot self-aggregate, it is capable of association with DS. Alternating IdoA and GlcA in DS can self-associate in the absence of divalent cations under physiological conditions (Fransson and Coster, 1979). Chemical modification of the sugar backbone, hydrogen bonding, and cation chelation are critical determinants of self-aggregation potential and solid-state structural conformation, necessary for conferring the biological information inherent in GAG biomolecules.
The chelating agent EDTA in the form of its disodium salt has minimal effect on mRNA retention, whereas acids greatly reduce mRNA (21) and should not be used. 3. Wash the sample in distilled water and transfer to EDTA for 10-14 d, with fresh changes of EDTA every 3 d (see Note 3).
Fixation solution 11 formaldehyde, 100 mM NaCl, 50 mM Tris-HCl, pH 8.0, 1 mM EDTA, 0.5 mM EGTA. Add formaldehyde immediately before use, from a 37 stock solution stabilized with 10 methanol. 5. Wash solution A 10 mM Tris-HCl, pH 8.0, 10 mM EDTA, 0.5 mM EGTA, 0.25 Triton X-100. 6. Wash solution B 200 mM NaCl, 10 mM Tris-HCl, pH 8.0, 1 mM EDTA, 0.5 mM EGTA. 7. Sonication buffer 10 mM Tris-HCl, pH 8.0, 1 mM EDTA, 0.5 mM EGTA. 10. Dialysis buffer 5 glycerol, 10 mM Tris-HCl, pH 8.0, 1 mM EDTA, 0.5 mM EGTA.
Thaw a 500-pL aliquot of chromatin, and adjust to 1 mL RIPA buffer, by sequential addition of 100 pL 10 Triton X-100, 100 pL 10 sodium deoxycholate, 100 pL 1 SDS and 100 pL 1.4 M NaCl. Allow 2 min gentle mixing between additions for equilibration of the chromatin into the new conditions. Finally add 50 pL 0.1 M Tris-HCl, pH 8.0, 50 pL 10 mM EDTA, and 10 pL 100 mM PMSF.
Nuclear incubation buffer 15 mM Tris-HCl, pH 7.5, 0.3 M sucrose, 15 mM NaCl, 5 mM MgCl2, 60 mM KCl, 0.1 mM EDTA, pH 8.0, 0.1 mM EGTA. Filter-sterilize (0.22 pm) and store at 4 C. Add fresh immediately before use 0.5 mM dithiothreitol (DTT), 1 mM PMSF (Sigma, St. Louis, MO, stock solution 200 mM PMSF in 100 ethanol). 5. Nuclear lysis buffer 10 mM Tris-HCl, pH 8.0, 100 mM NaCl, 1 mM EDTA, pH 8.0, 0.1 (v v) NP-40. Filter-sterilize (0.22 pm) and store at 4 C. Add fresh immediately before use 1 mM PMSF. 9. SW28 Ultracentrifuge tubes, 25 x 89 mm polyallomer (Beckman, Somerset, NJ). 10. CsCl buffer solution 0.5 (w v) Sarkosyl, 1 mM EDTA, pH 8.0. Filter-sterilize (0.22 pm) and store at room temperature. Add fresh immediately before use 1 mM PMSF. 13. 10X Dialysis buffer (pH 8.0) 0.5 M Tris, 20 mM EDTA. Combine dry ingredients and adjust pH with HCl. Autoclave and store at 4 C. For 1X dialysis buffer Dilute in autoclaved water. Add fresh immediately before use 1 mM PMSF.
The presence of a domain IV containing EF-hand motifs, of a C2-like domain and of the two non EF-hand calcium binding sites in domain IIa and IIb (Moldoveanu et al., 2002), suggests that calpain-3 does bind calcium. Nonetheless, early reports had indicated that it was rapidly degraded in the presence of EDTA (Sorimachi et al., 1993). The paradox was resolved by another study, that directly demonstrated calcium binding to calpain-3 using a gel overlay method, and showed that calpain-3 was stable in the presence of EGTA, autolytic cleavage already occurring at 500nM Ca2+(Branca et al., 1999). Therefore, calpain-3 has a Ca2+-affinity which is far higher than that of conventional calpains. Very recently, the calcium requirement for calpain-3 activity has been determined for two truncated isoforms p94 I-II, comprising domain I and II and the two inserts NS and IS1, and p94I-IIANS IS1 including domain I and II but lacking NS and IS1. The data have suggested cooperative binding of calcium at...
Given the central role of calcium and calcium-activated proteases in executing axon degeneration, the anticipation that calcium chelating agents and inhibitors of calpain significantly slow down the rate of Wallerian degeneration has been confirmed (George et al., 1995 Glass et al., 2002).
Mix adjustment, 0.48 baseline covariates adjustment, RR 0.41 baseline covariates and follow-up adjustment) 19 . One recent report demonstrated that a systematic program of education and mapping followed by AV fistula creation successfully converted 57.9 (70 121, intention to treat) of all catheter patients and 81.4 (70 81) of patients who agreed to venous mapping to a functioning alternative access 18 . An alternative approach is to make catheters safer by decreasing the bacteremia risk. In one report, mortality decreased by 76 and hospitalization for catheter-related bacteremia decreased by 63 with the routine application of an antiseptic antimicrobial solution (polysporin) at the catheter exit site 20 . Similar reductions in bacteremia have been reported with the use of muperacin ointment. Antimicrobial catheter lock solutions which decrease or prevent the formation of biofilm are also effective. Studies using citrate, taurolidine, gentamycin heparin, gentamycin EDTA have reported...
Mobility of linear (+) and relaxed, circular (o) DNA through 0.3 or 0.6 agarose gels, at 0.3 V cm for 30 or 40 h, respectively, in 0.1 M Tris, 0.09 M boric acid, and 1 mM EDTA. Figure 10.4. Mobility of linear (+) and relaxed, circular (o) DNA through 0.3 or 0.6 agarose gels, at 0.3 V cm for 30 or 40 h, respectively, in 0.1 M Tris, 0.09 M boric acid, and 1 mM EDTA.
TE buffer 10 mM Tris-HCl, pH 8.0 1 mM ethylenediaminetetraacetic acid (EDTA). 3. Solution of trypsin (0.25 ) and ethylenediamine tetraacetic acid (EDTA) (1 mM) from Life Technologies. 3. 10X RNA loading buffer 50 glycerol, 10 mM EDTA, 0.25 (w v) bromo-phenol blue, 0.25 (w v) xylene cyanol. Use DEPC water and keep at 4 C. 7. 20X MOPS buffer 0.4 M MOPS, pH 7.0, 100 mM sodium acetate, 20 mM EDTA. 8. 2X SSPE buffer with 0.1 sodium dodecyl sulfate (SDS) 1.5 MNaCl, 17.3 mM NaH2PO4, 2.5 mM EDTA, 0.1 SDS.
Thaw bacterial pellets in centrifuge bottles by the addition of a GET buffer (50 mM glucose, 25 mM Tris pH 8, 10 mM EDTA) containing 10 mg ml egg white lysozyme (Sigma L-6876), 10 ml per centrifuge bottle (20 ml per 500 ml culture). The bottle is vigorously vortexed to resuspend the pellet and create a homogeneous suspension. The cell suspension is transferred to a disposable 50 ml screw-cap tube using a Pasteur pipette. Any remaining clumps are broken up by rapid pipetting. 3. Produce complete lysis by the addition of an equal volume of 20 mM Tris pH 7.5, 0.2 M NaCl, 1 mM EDTA 1 deoxycholic acid, 1 NP-40. The bacterial solution and the lysis buffer should be gently rocked back and forth several times over several minutes to mix the solutions the solution should rapidly turn viscous (more of a gelatinous blob than a suspension). This indicates lysis and release of bacterial genomic DNA. 6. Add 10 ml of 0.5 TritonX-100 (TX-100), 1 mM EDTA to the tube and resuspend the IBs by pipetting....
Serum or dried whole blood but heparinized or EDTA plasma samples may be used with some instrumentation. To avoid preanalytical errors, puncture must take place in the appropriate place on the disinfected, dry heel, collecting free-flowing drops of blood that can fully saturate two 0.5-inch circles, and the filter paper must be properly labeled with the patient's name and date of birth, and the date and time of collection. The blood drops must dry thoroughly in a cool, dry area before being placed in a transport bag with the test requisition form. Plasma or serum can be held up to 1 day at room temperature, up to 7 days at 2 -4 C, and up to 30 days if frozen. Dried whole blood is stable for up to 1 week. Proper collection, handling, and storage of samples for thyroxine testing is necessary in order to avoid preanalytical errors.
If vitamins are added to a product to make a nutritional claim, it is critical that shelf-life studies are undertaken to prove that the overages added are sufficient to ensure that the label claims can be met at the end of product shelf life. This is important as none of the vitamins are fully stable in a soft drink environment and some, for instance vitamin C, are very quickly lost in the presence of oxygen. The addition of the fat-soluble vitamins to a soft drink also offers a formulation challenge to ensure that they are fully dispersed and that there are no problems with neck ringing during storage. Trace metals, particularly the transition elements, can also have a deleterious effect on vitamin shelf life, and sometimes metal scavengers, such as EDTA or phosphate salts, are added to improve the shelf life.
Figure 7 (A) Example of a Gadolinium complex demonstrating the chelation of the otherwise toxic Gd3+ metal. The free water interacts with the surrounding protons thereby locally changing the T1 and thus increasing the MR signal strength on T1 weighted images. (B) Example of a dextran coated iron oxide particle. Source From Ref. 4. Figure 7 (A) Example of a Gadolinium complex demonstrating the chelation of the otherwise toxic Gd3+ metal. The free water interacts with the surrounding protons thereby locally changing the T1 and thus increasing the MR signal strength on T1 weighted images. (B) Example of a dextran coated iron oxide particle. Source From Ref. 4.
Dissolve PEG-SH (or any SH-carrying compound) in oxygen-free phosphate-EDTA, pH 7.0, at a final concentration of 2 mM (if PEG-SH has a MW of 5000, then dissolve it at 10 mg mL). This solution should be used immediately after preparation. 2. In separate test tubes, mix 30 L of PEG-SH solution (or the solution containing SH) or 30 L of phosphate EDTA, pH 7.0 (as blank), and 970 L of phosphate-EDTA, pH 7.0. 1. Dissolve the reactive PEG in phosphate-EDTA, pH 6.0, at a final concentration of 2 mM (e.g., if the PEG molecular weight is 5000 Daltons, then dissolve it at 10 mg mL). 2. In separate test tubes, mix 500 L of reactive PEG solution or phosphate-EDTA, pH 6.0 (as a blank), and 500 L of cysteine solution.
(MALDI) and electrospray ionization (ESI). Despite its current importance in HP and HS structural analysis, only recently have there been significant advances in the development of MS as an analytical tool for structural characterization of these complex polysaccharides. Whereas historically, MS procedures for biological samples have largely been investigated and optimized using peptides and proteins, recent efforts have been aimed at identifying experimental conditions amenable to the analysis of acidic GAGs. Such an endeavor has proven critical since early on it was discovered that application of traditional mass spectrometric approaches to the analysis of GAG structure were generally ineffective. GAGs are difficult to detect as molecular ions due to differential chelation of positively charged metal ions (such as sodium) and because they possess the tendency to fragment extensively due to the loss of sulfate prior to detection. A number of techniques have been developed to analyze...
Formulation approaches have also yielded significant improvements. Ternary complex can be formulated by coating the polyplex with molecules addressing any of the rate-limiting steps discussed in Figure 9.1. For instance, PEI-PEG complexes have been mixed with lipiodol to produce stable water-in-oil emulsion 107 . When injected into an occluded femoral artery via a catheter, the emulsion can localize the complexes at the injection site and produce transgene expression mainly in the muscle rather than other organs. The expression level is 3-fold higher than that of PEI at one day post-injection. Adding human serum albumin to PEI-DNA during the complex formation leads to an intravenous formulation that can produce a positive, although very transient, transgene expression in the lung tissue of mice 108 . The administration can be repeated without inhibition of gene expression. It is speculated that as a major protein component of serum, HSA helps to minimize rapid opsonization of the...
The preferred specimen is whole blood that has been collected in EDTA, heparin, or fluoride anticoagulant. Capillary blood may be used for some procedures such as immunoassay. A hemolysate of washed RBCs is tested. Whole blood may be stored for 1 week at 4 C. Hemolystate may be stored for 4 to 7 days at 4 C or 30 days at -70 C.
Lysis buffer (10) 0.25 Triton X-100, 10 mM EDTA, 10 mM HEPES-NaOH, pH 6.8, 5-500 pM of 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB) (see Note 5), 0.5 mM phenylmethylsulfonyl fluoride (PMSF), 2 pg mL antipain, 2 pg mL aprotinin, 0.5 pg mL leupeptin. The protease inhibitors (PMSF, antipain, aprotinin, and leupeptin) and DTNB are added immediately before use. 5. Extraction buffer 0.25 Triton X-100, 0.12 M NaCl, 10 mM EDTA, 10 mM HEPES-NaOH, pH 7.5, 0.5 mM PMSF, 2 pg mL antipain, 2 pg mL aprotinin, 0.5 pg mL leupeptin. The protease inhibitors (PMSF, antipain, aprotinin, and leupeptin) are added immediately before use 5-500 pM DTNB may be added, as well (see Note 5). 8. Tris-acetate-EDTA (TAE) buffer 40 mM Tris-acetate, 2 mM EDTA. The pH should be between 8.2 and 8.5.
Dissolve IBs (from 500 ml of bacterial culture) in 8 ml of 8 M urea (20 mM Tris pH 8, 1 mM EDTA, 8 M urea) and filter through a 0.2 micron filter (Pall Serum Acrodisc, Fisher Scientific). 2. Chromatograph 4 ml of inclusion body solution on a Hi Load 16 60 Superdex 200 column. The column is run with 20 buffer B, giving conditions of 20 mM Tris, pH 8, 1 mM EDTA, 0.2 M NaCl. Electrophorese column fractions on an SDS-PAG and visualize the proteins by Coomassie blue staining. Pool peak fractions. 7. After spin labelling, add 8 ml of buffer A (8 M urea, 20 mM tris, 1 mM EDTA, pH 8.0) and chromatograph the spin labelled protein over the Source 15S as before. Collect the purified peak and store at -800C. 2. If EPR spectra are to be recorded at multiple steps during vimentin assembly, dialysis can be performed in a stepwise fashion 8 . Starting conditions are 20 mM Tris pH 8.0, 1 mM EDTA, 8 M urea (buffer A + 8 M urea). Vimentin dimers can be produced by dialysis against buffer A + 4 M urea....
Including tumor biopsies and whole blood can be obtained by standard procedures. Alternatively, commercially available system such as Ultraspec II RNA isolation system (Biotecx, Houston, TX) may be used. This system isolates total RNA by disruption and homogenization of samples with 14 M guanidine salts and urea followed by chloroform extraction. The sample is centrifuged and the upper aqueous phase containing the RNA is isolated followed by isopropanol precipitation. A proprietary RNATack resin that specifically binds RNA and then eluted with TE (Tris-EDTA, pH 7.4) buffer purifies the RNA. The RNA concentration is quantitated spectrophotometri-cally. The entire isolation can be completed in approx 1 h, which is a significant advantage over standard methods. RNA can also be extracted directly from lymphocytes obtained from whole blood. Concentrations of 10-15 ng of RNA are routinely obtained from 10 mL of whole blood comparing favorably to standard methods (55).
Serum, heparinized plasma, and urine may be tested. Anticoagulants, such as EDTA, citrate, or oxalate, should not be used because of their effect on the cofactor, calcium. Lowered pH may affect the stability of urine amylase therefore, the pH of stored urine must be maintained at 7.
Filtration of radioactively labelled compounds, such as 51Cr-EDTA, 131I-iothalamate and 99Tc-DPTA, gives a GFR value generally comparable to that of inulin clearance. The complex safety procedures and legislation governing the handling of such compounds has led to a decline in their use. The contrast agents iohexol (Krutzen et al. 1984) and isothalamate (Gaspari et al. 1992 Isaka et al. 1992) are eliminated from plasma mainly by glomerular filtration and have an excellent correlation with the plasma clearance of 51Cr-EDTA and inulin (Gaspari et al. 1995). Iohexol is more commonly used as it reportedly has lower allergenic potential. The most accurate estimate of GFR is obtained by sampling up to 600 min after injection, particularly in individuals with GFR 40 ml min 1.73 m2, sampling may be limited to only at 120, 150, 180, 210 and 240 min after injection.
Specimen collection for analysis of antibiotics allows for serum and other types of body fluids. The specimen of choice for gentamicin and tobramycin is serum, but EDTA plasma can be used. Heparin has been shown to deactivate gentamicin by forming an inactive complex that interferes with some immunoassay procedures. Most vancomycin methods call for serum but allow heparinized and EDTA plasma. Often only vancomycin trough levels are monitored for therapeutic range due to the drug's long distribution phase. The specimen of choice for chloramphenicol testing is serum, but heparinized and EDTA plasma or cerebrospinal fluid can be analyzed. Typically the trough level is used to evaluate therapeutic effects and the peak level, drawn 1 to 2 hours postdose, is used to monitor toxic levels of chloramphenicol. Often a clotted blood sample is to be collected, but the container should not have gel separation barriers, which leach out some drugs. Likewise, some drugs such as lidocaine,...
Grow cells in a T-75 flask until they are 70-80 confluent. Aspirate media and wash cells once with 15 mL PBS. Add 2 mL trypsin-EDTA and incubate plates at 37 C for 2-5 min. Resuspend cells in DMEM to a final concentration of 3.3 o 105 cells per mL (HeLa cells) or 2.64 o 105 per mL (BS-C-1 cells). Dispense 30 pL of cell suspension into each well (providing 10,000 cells per well for HeLa cells, or 8000 cells per well for BS-C-1). For luciferase assays, dispense cells into 384-well white plates for imaging assays, use 384-well black plates with clear bottoms.
Change, but the peak concentration of these agents is increased and the risk of toxicity enhanced as a results of volume of distribution (Vd) alterations. The effects of Vd changes may be ameliorated by correction of anaemia, when this is present. Several studies have shown that anaemia is an independent risk factor for chemotherapy-induced myelodepression 28 , as many agents bind to red blood cells consequently, anaemia is associated with increased concentration of circulating free drug. A decline in the glomerular filtration rate (GFR) is almost universal with aging, and may lead to an increased half-life of cytotoxic compounds, such as carboplatin, methotrexate, and bleomycin, whose parent compounds are excreted through the kidneys, and drugs that give origin to active or toxic metabolites excreted from the kidneys. For example, 80 of the activities of idarubicin and daunorubicin are metabolised in the liver and excreted from the biliary tract, but is due to renally excreted...
Lysis buffer 1 Nonidet P-40, 20 mM Tris-HCl at pH 7.4, 150 mMNaCl, 1 mM ethylenediaminetetraacetic acid (EDTA). Store at 4 C. Add protease inhibitors (antipain, 1 g mL , leupeptin 1 g mL , chymostatin 1 g mL , pepstatin 1 g mL , phenylmethyl sulfonyl fluoride 1 mM ) immediately before use.
Silverman's laboratory reported hCA II activation by histidine (Silverman et al. 1978), but subsequently considered their discovery an artefact owing to the ethyl-enediaminotetraacetic acid (EDTA) added in the buffer, which might form complexes with the adventitious Cu2+ possibly present in the protein preparation, thus restoring the activity of the enzyme (heavy metal ions act as micromolar inhibitors of most CAs Tu et al. 1981). In the light of this study (Supuran et al. 1991), the initial report by Silverman's group regarding hCA II activation with histidine (Silverman et al. 1978) was proposed to be authentic. It was explained that the controversial results of Tu et al. (1981) were because of the experimental protocols used, EDTA probably possessing a competitive suppressing effect for the histidine activating effect (Supuran and Puscas 1994).
Dissociate monolayers with trypsin EDTA (see Note 1) and resuspend cells in complete medium. 1. Most cell types require a 0.25 (w v) trypsin 0.2 (w v) EDTA solution prepared in sterile Hank's Balanced Salt Solution (HBSS) or 0.9 (w v) NaCl to detach cells and chelate Ca2+ and Mg2+ ions that could hinder the action of trypsin.
SAU-1000 7M urea (deionized), 20 mM sodium acetate, pH 5.2, 1 M NaCl, 5 mM 2-mercaptoethanol, 1 mM Na-EDTA. Pass through 0.4- im filters before use. 6. SAU-200 7M urea (deionized), 20 mM sodium acetate, pH 5.2, 0.2M NaCl, 5 mM 2-mercaptoethanol, 1 mM Na-EDTA. Pass through 0.4- m filters before use. 7. SAU-600 7M urea (deionized), 20 mM sodium acetate, pH 5.2, 0.6M NaCl, 5 mM 2-mercaptoethanol, 1 mM Na-EDTA. Pass through 0.4- m filters before use.
50X Tris-acetate buffer 2 M Tris-acetate, pH 7.8, 1 M sodium acetate, 0.1 M EDTA. 2. 20X TBE buffer 1 M Tris-base, 1 M boric acid, 20 mM EDTA pH should be around 8.3. 4. 100X TE buffer 1 M Tris-HCl, pH 7.5, 0.1 M EDTA. 5. 100X TAE buffer 0.67 M Tris-acetate, pH 7.5, 0.33 M sodium acetate, 0.1 M EDTA.
Available radionuclide agents excreted only by glomerular filtration include iothalamate, diethylenetriamine pentaacetic acid (DTPA) and ethylenediamine tetraacetic acid (EDTA). Most accurate clearance values are obtained using standard clearance techniques (as described previously for inulin) including timed blood and urine samples. 125I-iothalamate (614 dalton) may also be administered as a subcutaneous bolus injection obviating the need for a constant infusion. It provides GFR values identical to those obtained with inulin. Because of the prolonged half life of the isotope (60 days), concomitant Lugol administration is required to protect the thyroid. Values obtained with 51Cr-EDTA (292 dalton) are 10 lower than inulin, perhaps because of in vivo protein binding, tubular reabsorption, or in vivo dissociation. The disadvantage in using 99MTc-DTPA (393 dalton) is that its short half-life of 6 hours requires preparation immediately before administration and prompt counting of samples....
Direct replacement of red blood cells through transfusion is the cornerstone of palliating anemia-related symptoms in MMM. Currently, there are no data to support the routine use of iron chelation therapy for prevention of secondary iron overload in these transfusion-dependent individuals. Indeed, there are no data demonstrating definitive end-organ toxicity from iron overload in MMM patients. Unfortunately, the
Thaw bacterial pellets in 24-well blocks at room temperature. While waiting, add protease inhibitors, lysozyme, and Benzonase to the chilled lysis buffer 1 mg mL lysozyme, 10 units Benzonase mL, 2 pL mL protease inhibitor cocktail (no ethyl-enediamene tetraacetic acid EDTA ), and 1 mM PMSF. Keep on ice.
Whether VSP develops must depend in part on the quantity of spasminogen(s) released on the abluminal side of the involved vessels. The RBC obviously disintegrates in the alien subarachnoid space more quickly than it would in the blood. The mean survival time is reduced to approximately I week from 4 months. Passage of intact RBC out of the subarachnoid space in humans is unlikely to occur. Disruption of the RBC membrane may occur because of osmotic forces and or because of phagocytosis, which is triggered by the loss of protective or the addition of targeting molecules on the RBC surface. It is likely that the cause of VSP is oxy- and or deoxyHb and or heme since they are the vasoconstrictors produced in by far the greatest amounts as hemolysis proceeds. There is evidence that these substances can permeate the vascular wall from the adventitial side through to the endothelium. How extracellular Hb causes contraction of the vascular smooth musclc cells is unclear possibilities include...
Essentially all circulating plasma iron normally is bound to transferrin. In addition, two-thirds of serum transferrin exists as apotransferrin and will quickly capture the free iron which is released from the cell 42 . This chelation serves three purposes it renders iron soluble under physiologic conditions, it prevents iron-mediated free radical toxicity, and it facilitates transport into cells.
B-type natriuretic peptide (BNP) and the N-terminal fragment of its prohormone (NT-proBNP) have emerged as the preferred candidates for diagnosis of heart failure, as well as other clinical applications. Several commercially available assays have been developed for point-of-care determination as well as for high-throughput automated laboratory platforms. Knowledge of preanalytic and analytic issues as well as sources of inter- and intraindividual variability in BNP and NT-proBNP is crucial for clinicians to allow correct interpretation of test results in routine practice. A few practical points for the clinical use of BNP and NT-proBNP include the following Blood sampling may be performed without a standardized period of rest or posture. However, heavy physical exercise should be avoided before blood sampling. Blood for BNP determination must be collected in EDTA-coated plastic tubes, whereas for NT-proBNP serum or plasma collected in glass or plastic tubes is acceptable. Although the...
The in vitro stability of both BNP and NT-proBNP is sufficient for routine clinical use. The in vitro stability of BNP is dependent on the assay used for determination (see Issues for Assay Development). BNP is stable in EDTA whole blood at room temperature for 4 h (Biosite and Abbott assays), and at 4 C for 24 h (Bayer assay). EDTA plasma is stable at 4 C for 24 (Abbott assay) and 48 h (Bayer assay). A significant decrease in plasma BNP concentrations was noted when BNP was measured after 24 h of storage at 4 C with the Biosite assay (12). If samples are not to be analyzed within several hours, it is recommended that the plasma be frozen at or below -20 C. NT-proBNP is stable in whole blood or in EDTA or heparinized plasma samples for 2 to 3 d at room temperature (18,19). NT-proBNP is stable in serum samples if serum is separated from cells within 24 h. NT-proBNP is stable in serum or plasma samples for several days at 4oC and for 12 mo at or below -20 C (12,18,19).
For most purposes, an isoosmotic medium containing 0.25 M sucrose, 1 mM EDTA, 10 mM Tris-HCl, pH 7.4 may be used for any soft tissue or cultured animal cell. There are a number of minor variations such as adding EGTA instead of, or in addition to, EDTA and substituting Tris by an alternative organic buffer (Hepes or Tricine). Such modifications do not materially affect the result of the fractionation procedure they are normally introduced to be more compatible with some subsequent add-on procedure or analysis. Others, summarized in Table 4.1, are more critical to the isolation of a particular organelle or use of a particular tissue or cell type. The presence of divalent cations is detrimental to the functioning of mitochondria hence EDTA is regularly included in media for the isolation of these organelles (and also lysosomes and peroxisomes). Mannitol-containing media (sometimes also supplemented with K+) are also suited to the preservation of oxidative phosphorylation in...
Are accessible in chromatin and which sites are protected (8). DNase I (bovine pancreas) is a double strand specific endonuclease with sequence specificity for AT-rich regions. It requires divalent cations (Mg2+, Ca2+, Mn2+), attacks DNA in the minor groove and cuts one of the two strands. A double strand break is observed if a second cut occurs on the other strand in close proximity of the first cut (6). In nucleosomes, DNase I leads to a cutting every 10 bp whenever one of the DNA-strands faces the surface (9). Hence, DNase I is the appropriate enzyme to analyse the rotational setting. Apart from the enzymes, various chemical reagents which induce DNA strand breaks were tested. Most frequently used is methidiumpropyl-EDTA (MPE.Fe(II)) for which detailed protocols have been published (10). In general, at sites of ambiguous and unclear interpretation with one reagent, a combination of MNase, DNaseI and MPE.Fe(II) is recommended.
Hybridization buffer 52.5 mL 1 M NaP pH 7.2, 12 mL H2O, 35 mL 20 SDS, 0.2 mL 0.5 M EDTA, pH 8.0, 1 g bovine serum albumin (dissolve by 5-10 min incubation in 65 C water bath this may form some precipitate on standing but can be redissolved at 65 C). 4. Church Gilbert wash 1 350 ml H2O, 20 mL 1 MNaP , 125 mL 20 SDS, 1 mL 0.5 M EDTA, pH 8.0. 5. Church Gilbert wash 2 910 mL H2O, 40 mL 1 MNaP , 50 mL 20 SDS, 2 mL 0.5 M EDTA, pH 8.0.
The abbreviations used are AAGE6, 250 mM ammonium acetate, 6 M guanidine hydrochloride, 10 mM EDTA (pH 6.0) AAGE9, 250 mM ammonium acetate, 6 M guanidine hydrochloride, 10 mM EDTA (pH 9.0) ABTS, acid) Ado, adenosine BPB, bromophenol blue BSA, bovine serum albumin DBD, DNA binding domain DHBB, dihydroxyboronyl Bio-Rex DTT, dithiothreitol ELISA, enzyme-linked immunosorbent assay HEPES, acid HPLC, high-performance liquid chromatography PES, phenazine ethosulfate PMSF, phenylmethylsulfonyl fluoride MNNG, 1-methyl-3-nitro-1-nitrosoguanidine MTT, phenylmethylsulfo-nylfluoride, bromide NAD,
Buffer A 50 mM Tris-HCl, pH 7.6, 150 mM NaCl, 1 mM EDTA, 1 mM EGTA, 5 glycerol, and protease inhibitors 6 g mL antipain, 4.3 g mL leupeptin, 4.5 g mL aprotinin, 5 g mL bovine trypsin inhibitor, 5 g mL pepstatin, 6 g mL chymostatin, 350 g mL benzamidine-HCl, 1 mM PMSF. 6. Buffer D 50 mM Tris-HCl, pH 8.0, 0.5 mM EDTA. 11. Buffer F 50 mM Tris-HCl, pH 8.0, 0.5 M EDTA, pH 8.0, 150 mM NaCl, degassed and filtered through a 0.22- M filter.
The choice of the mobile phase is very important, as fluorescence is sensitive to fluorescence quenchers. Highly polar solvents, buffers, and halide ions quench fluorescence. The pH of the mobile phase is also important to fluorescence efficiency for example, quinine and quinidine only display fluorescence in strongly acidic conditions, whereas oxybarbiturates are only fluorescent in a strongly alkaline solution 67,68 . Due to the stability of the chromatographic sorbents, the use of very acidic or basic mobile phase may not be possible. One alternative is to alter the effluent pH postcolumn. Postcolumn addition of sulfuric acid has been used for the assay of ethynodiol diacetate and mestranol in tablets 69 . Another example is the determination of tetracycline antibiotics in capsules and syrup where EDTA and calcium chloride were added to enhance fluorescence 70 . The selectivity of amperometric detection has been useful in simplifying the sample pretreatment steps in the...
Covalent bonding of an amino acid to inulin (Figure 5.6) allows further chemical modification of the polymers for possible medical use, peptide synthesis, or producing chelating agents for metal ions. The terminal primary amino acid could be more reactive toward acylating agents and potentially allow the attaching of a cross section of molecules of interest. Such compounds are attractive since both amino acids and inulin are expected to be nontoxic, biocompatible, and biodegradable
Inulin can be modified to compounds that display good heavy metal complexing properties similar to ethylene diamine tetra-acetic acid (EDTA) but with better biodegradation properties (Bogaert et al., 1998). Inulin is first oxidized using sodium periodate to the dialdehyde, and then reduced to a polyol using Pt C and hydrogen. The polyol can then be modified with carbon disulfide to form xanthate or with SO3-pyridine to obtain an inulin sulfate. Alternatively, the dialdehyde can be aminated with diaminoethane and sodium cyanoborohydride and the product reacted with monochloroacetic acid sodium salt to form carboxymethylamino inulin. Each of these compounds can be used to precipitate heavy metals.
Modification of the checkerboard DNA-DNA hybridization method 38 . In brief, subgingival plaque samples are obtained with the help of periodontal curettes and placed in individual pre-labeled bar-coded tubes containing 0.1 ml TE buffer (10 mM Tris-HCl, 1 mM EDTA, pH 7.5) and 0.1 ml of 1 M NaOH. Samples are stored at -80 C until assay. The sample DNA was denatured through boiling for 5 min and neutralized using 0.8 ml 5 M ammonium acetate. The DNA was placed into the slots of a Minislot device and thereby deposited as 'lanes' onto a Roche Diagnostics nylon membrane. The DNA was then fixed to the membrane by exposure to ultraviolet light. Pooled DNA of known bacterial numbers (105 and 106 CFU ml) for each one of the microorganisms included in the analysis were deposited with the patient's samples. Digoxigenin-labeled whole genomic DNA probes were prepared for each of the reference strains using a random primer technique. For these analyses the level of all 8 organisms was summed to...
1.5 X binding buffer 50 mM Tris-HC1 (made from a 1 M stock solution, pH 7.5), 5 mM EDTA, 50 mM MgCl2, 25 glycerol (v v 31.5 g 100 mL). Adjust pH to 6.8 with HCl and filter-sterilize the solution. 4. IPTG-elution buffer 10 mM Tris-HCl (made from a 1 M stock solution, pH 7.5), 1 mM EDTA, 125 mM NaC1. Filter-sterilize and store at room temperature. 26. TE buffer 10 mM Tris, pH 8.0, 1 mM EDTA, pH 8.0 (autoclaved). 33. 10X DIANA buffer (100 mL) 25 mL 1 M Tris-HCl, pH 8.0, 30 mL 5 M NaCl, 2 mL 0.5 M EDTA, 5 mL 1 M MgCl2. Autoclave, allow to cool to room temperature. Add 0.5 mL Tween20 and store at 4 C.
A cornerstone of the treatment of CKD patients is the use of phosphate-binding agents. Aluminum is rarely used any more, but calcium, magnesium, and lanthanum-based agents all pose the possibility of chelation of drugs as well as the intended gastrointestinal phosphorus. Tetracycline chelation to antacids is well known to clinicians, but tetracycline is not used often in the CKD patient population. Of more importance to caregivers of CKD patients is the well-described drug interaction
Chronic PRBC transfusion therapy can result in iron overload, and prevention of hemochromatosis should be considered in patients with stable disease. Liver biopsy is the gold standard for assessing iron overload, but it may not be feasible in some patients because of thrombocytopenia or other medical concerns. Superconducting quantum interference device imaging can quantitate hepatic iron deposition, but this technology is available at few sites throughout the world. MRI of the liver or heart can be used to document iron overload,6 and despite its limitations, serial serum ferritin levels can also be used to estimate systemic iron burden. Patients with chronically elevated ferritin levels (1500-2500 ng mL or greater), and those who have received 25-50 units of PRBCs, should be considered for iron chelation therapy with subcutaneous desferoxamine.7'8 Unfortunately, because of the cost, discomfort, and time involved in its administration, desferrioxamine therapy is frequently refused or...
The causes of thrombocytopenia can be divided into (a) decreased platelet production, (b) decreased platelet survival, (c) sequestration (hypersplenism), and (d) dilutional. Automated cell counters report spurious thrombocytopenia in approximately 0.1 of patients. This is generally a result of platelet clumping after drawing blood into the anticoagulant ethylenedi-aminetetraacetic acid (EDTA). Confirmation can be obtained by identifying platelet aggregates on peripheral blood smear and by obtaining a normal platelet count after using citrate or heparin as an anticoagulant. Therefore, reviewing the peripheral blood smear is very important for identifying spurious thrombocytopenia. Impaired platelet production is caused by a bone marrow abnormality, such as infiltration caused by malignancy or myelofibrosis, marrow hypoplasia as a result of chemicals, drugs, or radiation, and viruses. In these cases, a deficit of platelet production is rarely seen without abnormalities in the production...
Effectively remove the cellular components from semilunar valve tissue while retaining the majority of the ECM components (primarily collagens, elastin and the less water soluble proteoglycans). The following decellularization methods effectively remove endothelial cells and cuspal interstitial cells however, cardiac myocytes and arterial wall smooth muscle cells are variably present after processing 1) anionic detergents 2) non-ionic detergents 3) trypsin EDTA and 4) deionized water. These agents are frequently used in combination with protease inhibitors. In addition to removing the cellular components, residual nucleic acids are also removed from the tissue by DNase and RNase digestion. The tissues are then further rinsed to facilitate removal of cellular remnants and tissue processing reagents. The various decellularization processes may also reduce the immunogencity of allograft and xenograft tissues however, this belief has not been substantiated by extensive studies assessing...
Early electrophoretic analyses of hyaluronan and other glycosaminoglycans were designed to separate polysaccharides primarily according to charge density (33-35). Size separation had not been established by analysis of well-characterized samples differing solely in molecular weight. In 1984, three separate groups (36-38) reported high-resolution separation of glycosamino-glycan oligosaccharides according to size. In each case, a polyacrylamide gel was used to separate oligosaccharides into discrete bands, with adjacent bands in the final pattern differing in size by one disaccharide repeat. The gel composition varied from 10 to 25 acrylamide and the continuous buffer systems used were 50-100 mM Tris-borate, pH 8.3, with 1-2.4mM EDTA or 100 mM Tris-glycine, pH 8.9, with 1.25 mM EDTA. If the glycosaminoglycan fragments were radiolabeled, the separation patterns were visualized by fluorography of the gel after incorporation of a fluor and subsequent drying of the gel. Separation patterns...
In this method separation of Cr (IV) or Cr (III) requires complexation with either cyclohexanediamine-tetraacetic acid (CDTA) or ethyldiaminetetraacetic acid (EDTA) to to cause the chromium species to migrate towards the cathode. Using CDTA and direct detection at 240 nm gave 19 and 59 ppb (ng mL) detection levels for Cr (VI) and Cr (III), respectively. About 10-fold lower detection limits noted when EDTA used (23). Although the limit of sensitivity for the method using EDTA is good, another one to two orders of magnitude is still required for CE to be clinical useful.
Prepare 100 l mixture of myosin (10 g with final concentration 0.1 mg ml) and S100A4 (50 ig) in a buffer (0.6 M NaCl, 10 mM MES pH 6.2, 1 mM DTT) containing 1 mM CaCl2 or 5 mM EDTA. 2. Dialyse proteins for 5 h at RT against 200 ml of buffer, 10 mM MES pH 6.2, 1 mM DTT, 1 mM CaCl2 or 5 mM EDTA and different NaCl concentrations, 50, 100, 200, 300 and 400 mM.
Although GdCl3 is very toxic, chelating Gd(III) (as with DTPA) largely reduces its toxic profile (32-34). With a high thermodynamic stability constant (KGd-L 1026 for Gd-DTPA), the chelated metal complex is essentially inert and is cleared at a significantly faster rate than the rate of dissociation of the metal ion from the complex. However, the plasma clearance rate of chelated Gd is still sufficiently slow to provide ample contrast for MRI applications. Thus, the chelation process transforms an otherwise highly toxic salt into a useful diagnostic reagent (35).
Whole blood is the specimen of choice for recent exposure. A 12- or 24-hour timed urine collection in a mercury-free container is the specimen of choice for long-term exposure. The timed urine may be helpful in determining recent or long-term exposure and the need for therapy. Although there is no antidote to mercury, early chelation therapy may be used to lessen the effects of exposure. Dimercaprol has been used effectively as a chelator of inorganic and aryl organic mercury. An announcement in the local newspaper brought many concerned individuals, including one fisherman, to their physicians, who requested mercury screening on blood and urine specimens. The laboratory technician instructed the patient on the proper collection of urine for mercury testing. The technician had already drawn a blood sample in a metal-free, EDTA-containing tube for blood analysis for mercury.
Wash solution 1 50 mM Tris-HCl, pH 8.0, 2 mM EDTA, pH 8.0, 0.2 Sarkosyl. Add fresh immediately before use (do not add when preparing 20 staph A cell stock) 1 mM PMSF, 0.5 pL mL aprotinin (Sigma), 2.5 pg mL leupeptin (Boehringer Mannheim Stock solution 5 mg mL in H2O), 0.25 pg mL pepstatin (Boehringer Mannheim Stock solution 0.5 mg mL in ethanol) 8. Protease solution 50 mM Tris-HCl, pH 7.5, 10 mM EDTA, pH 8.0, 0.3 SDS. Add immediately before use 1 mg mL proteinase K (Boehringer Mannheim). 11. 5X Loading dye 20 (w v) sucrose, 1X TBE, 0.1 (w v) Bromophenol blue, 5 mM EDTA, pH 8.0. Filter-sterilize (0.22 im) and store at room temperature. Add 1 L mL RNase (Boehringer Mannheim DNase free, 1119-915) when diluting to 1X loading dye