contrast contrast media and x ray absorption

... scanning calorimetry (DSC); X- ray powder diffraction (XRPD); combined, simultaneous, and dynamic differential scanning calorimetry /X- ray powder diffraction (DSC/XRPD); and high performance liquid ... of Mixtures of Polymorphs and Potential New Solids Forms By using the combined and dynamic DSC/ XRPD, several mixtures of disodium salt samples were identified, and the components of these mixtures ... mixture of hydrated Forms I and IV (sample 8) Figure 31 DSC of mixture of Form III monohydrate and Form IV hydrate (sample 56) Figure 32 Superimposed XRPD of mixture of Form III monohydrate and...

Ngày tải lên: 14/02/2014, 03:20

... residues 29, T34 and E131 are shown The hydrogen bonds between N29 and Oc and T34 and Oc, and between N29 and Nd and E131 and Oe2, in the wild-type protein are shown as green broken lines, and the ion ... the protein, and a and b represent the a helix and b strand, respectively The side-chains of the mutated and parent amino acid residues at the six mutation sites are shown D39 ⁄ G39 and M76 ⁄ V76 ... 6·-RNase HI and wild-type proteins (full line) and between molecules C and D (broken line) a Helices and b strands are indicated by bars helices, and around Gly128 in a loop between the aV helix and...

Ngày tải lên: 18/02/2014, 13:20

... decreased in the series b-d-xylohexaose (Xyl6) > b-d-xylopentaose (Xyl5) > b-d-xylotetraose (Xyl4) > b-d-xylotriose (Xyl3), with no detectable afnity for b-d-xylobiose (Xyl2), which is consistent ... (Da)a TRX I (none) None S-Xyl2-Me S-Xyl3-Me S-Xyl4-Me S-Xyl5-Me None S-Xyl2-Me S-Xyl3-Me S-Xyl4-Me S-Xyl5-Me None S-Xyl2-Me S-Xyl3-Me S-Xyl4-Me S-Xyl5-Me 19046.920 n.b 19508.080 19656.081 19804.091 ... FEBS J Janis et al ă Thioxylo-oligosaccharide binding to xylanases Fig MS titration curves for TRX I (5 lM), TRX II (10 lM) and CTX (10 lM) with S-Xyl5-Me, S-Xyl4-Me and S-Xyl3-Me (initial concentrations...

Ngày tải lên: 07/03/2014, 17:20

... Table 1), immediately suggesting the presence of three (N/O)-ligands and one sulfur ligand Fixing the number of zinc ligands to the nearest integer values (i.e and for (N/O) and sulfur ligands, respectively) ... the nonsulfur ligands, possibly the oxygen of coordinated H2O or hydroxide EXAFS of two MtaA mutants, Cys239 Ala and His237 Ala Fig Normalized XANES spectra of wild-type MtaA and of two MtaA ... the absence and presence of coenzyme M (apparent Km ẳ 40 lM) by XAS at the zinc K-edge EXAFS and XANES spectra are shown in Figs and 2, respectively The Fourier transforms of the EXAFS spectrum...

Ngày tải lên: 17/03/2014, 23:20

... 164 x, y,z x +1,y,z x +1,y,z 1 -x, y +1 ⁄ 2,-z x, y,z x, y,z x, y,z x, y,z x- 1,y,z 1 -x, y-1 ⁄ 2,1-z x, y,z x, y +1,z x, y +1,z x, y-1,z x, y-1,z x, y,z 1 -x, y-1 ⁄ 2,1-z x, y,z 1 -x, y +1 ⁄ 2,-z x, y +1,z x, y,z x, y-1,z ... x, y-1,z x, y,z x, y-1,z 3.024(4) 2.783(5) 3.016(4) 3.138(5) 3.021(5) 2.776(5) 3.273(5) 3.122(5) 2.814(4) 2.848(5) 3.221(4) 2.767(5) 3.083(5) x, y,z x, y,z 1 -x, y-1 ⁄ 2,-z 1 -x, y-1 ⁄ 2,-z x, y,z x, y,z x, y,z ... characteristics of EM2 and EM2OH in DMSO, TFE, H2O (pH 2.7 and 5.2) and DPC micelles (pH 3.5 and 5.2) Open and fold represent the conformations rS and n7 in parentheses indicate the reverse S- and numerical...

Ngày tải lên: 30/03/2014, 20:20

... Crystallography 39 a X X NH X = C,N,O X = C,N O O O O N H O X Y Y X N N NH C=O C O C C NH Y X b C=O NH C C O NH C X Y Y N X H N H N O N Pyrrole Imidazole Furan Benzene N N H N H N N N Pyridine Cyclohexane Pyrimidine ... trials Drug and latest reported development Company Target Phase PLX-4032 Plexxikon B-Raf V600E Phase ABT 263 Abbott Bcl-2/Bcl-xL ABT 869 Abbott VEGF and PDGFR AT9283 Astex Aurora AT7519 Astex CDKs ... 36–45], and are also covered in more depth by Wyss and coworkers [46] 2.2.2 X- Ray Crystallography X- ray crystallography is covered in detail by Bauman et al [47], Davies and Tickle [48], and Hennig...

Ngày tải lên: 29/05/2014, 23:54

... lobular carcinoma and in-situ ductal carcinoma studied in this work is referred to as glandular tissue Therefore, it is expected different peak positions will exist for carcinoma and fibrocystic ... CRM, Hufton AP and Dance DR Breast cancer diagnosis using scattered X- rays J Synchrotron Rad 2000; 7: 348-352 Malden CH, Speller RD, et al A CdZnTe array for the detection of explosives in baggage ... (second edition) Philadelphia: Lippincott Williams and Wilkins 1999 Kidane G, Speller RD, Royle GJ, Hanby AM X- ray scatter signatures for normal and neoplastic breast tissues Phys Med Biol 1999;...

Ngày tải lên: 02/11/2012, 11:08

... Protein–ligand and water-mediated protein–ligand hydrogen bond interactions (broken lines) that stablize the pantoate molecules in site I and site II of nPS Oxygen atoms of pantoate and water ... form of nPS using X- ray crystallography, as described below A Solution and refinement of the structure using X- ray crystallography B The crystal structure of the pantoate–nPS complex was solved by ... density maps and facilitate further rebuilding and improvement of the molecular model, until no unexplained electron density remained, and the Rcryst and Rfree values converged at 18.9% and 24.4%,...

Ngày tải lên: 16/02/2014, 09:20

... when the complex is formed The ligands cellobiose, cellotetraose and cellohexaose were studied Results and Discussion The crystal structure of CtCBM11, the binding cleft and its ligand specificity ... in the X- ray structures of CBM4 and CBM17 complexed with cellopentaose and cellohexaose, respectively [13,23] The involvement of the tyrosine residues in the stabilization of the complex cannot ... two six-stranded anti-parallel b-sheets that form a convex side (b-strands 1, 3, 4, 6, and 12) and a concave side (b-strands 2, 5, 7, 8, 10 and 11) The concave side is decorated by the side chains...

Ngày tải lên: 18/02/2014, 17:20

... a model and the experimental data: N X IðSj Þ À Iexp ðSj Þ2 v2 ¼ ð8Þ N À j¼1 rðSj Þ where for each momentum transfer value, Sj, I(Sj) is the theoretical scattering, Iexp(Sj) is the experimentally ... solution X- ray scattering These pieces were modelled into the AA and BD dimers as extended polypeptide [26], and produced an improvement in the fit of the AA model at S values between 0.15 and 0.2 ... Kd and k were varied to fit the experimental data ð5Þ ð6Þ nm)1 With a 3-m sample–detector distance, useful data began at an S value of 0.04 nm)1 and the linear Guinier region extended to approximately...

Ngày tải lên: 22/02/2014, 07:20

... structure and unfolding upon replacing the axial Met ligand with a Lys in the M100K variant of cyt c-550 from P versutus We describe three X- ray structures, one of the ferric wild type (wt) and two ... electronic absorption band at 623 nm at pH 4.5 (B) The peroxidase activity, pH 4.5 and (C) peroxidase activity at pH 7.0 Data for the ferric wt protein is included for comparison, and all data ... substituents are extremely sensitive to the chemical nature of the axial ligands to the hemeiron [41] Upon replacing the native Met ligand with either an exogenous or protein-based ligand a change...

Ngày tải lên: 07/03/2014, 17:20

... is known from X- ray structural analysis of wild-type cyt b5 [21] that the core consists of b-strand III (Tyr27–Leu32), b-strand II (Thr21–Leu25), b-strand I (Lys5–Tyr7) and a-helix I (Thr8– His15) ... absorption in the Soret band too, but shows the absorption contributed from aromatic amino acids in the near UV region [35] The concurrent existence of the Soret band absorption at 418.8 nm and ... stage A random sample of 10% of the X- ray data was excluded from the refinement and was taken as the test data set, and the agreement between the calculated and observed structure factors of the...

Ngày tải lên: 08/03/2014, 10:20

... superfamily of metzincin which exhibits some typical structural features, such as the Met-turn and active-site consensus HExxHxxGxxH sequence [15–17] Some organisms and mammalian tissues recently ... Huber, R & Bode, W (1995) X- ray structures of human neutrophil collagenase complexed with peptide hydroxamate and peptide thiol inhibitors Implications for substrate binding and rational drug design ... off by a solvent mixture of trifluoroacetic acid and ethanedithiol, and solvent was evaporated to dryness The resins were then washed with cold ether and the peptides were extracted with 5% acetic...

Ngày tải lên: 08/03/2014, 23:20

... Docking experiment with androstenol and androstenone The previously identified natural ligands androstenol and androstenone have been built with the program ACD/CHEMSKETCH [18] The parameter and topology ... Stereoview of SAL X- ray structure in ribbon representation The helix is in red, strands are blue and turns or coil are yellow The GlcNAc residue bound to Asn53 is in white ball -and- stick, and the serendipitous ... the model of the complex of androstenol bound in SAL, with in (A) and (C) the ligand in position ÔinÕ, with the OH pointing inside the cavity and, in (B) and (D) the ligand in position ÔoutÕ,...

Ngày tải lên: 17/03/2014, 17:20

... residues Glu35 and Asp52 (numbering for HEWL), for BSL2 and other lysozymes, with propka 2.0 [16] The predicted pKa values were 6.15 and 4.27 for BSL2, 5.93 and 4.20 for HEWL, and 4.89 and 3.84 for ... acetate (for pH and 5) and sodium phosphate (for pH and 7) buffer The ionic strength of each buffer was adjusted to 0.1 [40] Lysozyme solution and M lysodeikticus suspension were mixed, and the decrease ... criteria: maximal ˚ ˚ distances of 3.5 A for donor–acceptor and 2.5 A for hydrogen–acceptor, and minimal angles of 60° for donor– hydrogen–acceptor and 90° for hydrogen–acceptor X Water-mediated...

Ngày tải lên: 23/03/2014, 04:21

... LiOH provided the expected products PAH and FPAH as lithium salts in 28% and 15% overall yield, respectively X- ray crystallography Recombinant T brucei enolase was expressed and purified as previously ... 20 mm of ligand (PEP, PAH or FPAH) for and flash-cooled X- ray diffraction data were collected from two native crystals (referred to as sulfate_2 and sulfate_3 in Table 1) and four ligand-cocrystallised ... sulfate_2, PEP and PAH_1 structures is shown in Fig Unexpected variability in inhibitor complex structures Comparison of the substrate and inhibitor complexes shows that the His156-out and His156-in...

Ngày tải lên: 23/03/2014, 07:20

... central six-strand mixed b sheet (b2, b1, b3, b5, b6 and b4; b5 is antiparallel to the others) flanked by three a-helices (a1, a9 and a8) on the inner side and by two a-helices (a2 and a3) and two ... 1P74, 1WXD, 2EGG, 2HK7, 2HK8 and 2NLO), (b) binary complex bound with either cofactor (1NPD, 1NVT, 1NYT, 1O9B, 1P77, 1VI2 and 2CY0) or substrate (2D5C, 2GPT and 2O7Q) and (c) inactive (2HK9_A and ... amides of Asn58 and Asn85 The C4-hydroxyl group of shikimate interacts with the carboxylate group of Asp100 and with the side-chain amides of Asn85 and Lys64 The C3-hydroxyl group forms extensive hydrogen...

Ngày tải lên: 30/03/2014, 02:20

... f14 x; ZÞ ¼ f13 x3 ; ZÞ x ; x x x4 x3 where < f21 x; ZÞ ¼ a expðÀb1 x þ ðZ À aÞ expðÀcxÞ; x x1 x x x2 F2 x; ZÞ ¼ f22 x; ZÞ ¼ f21 x1 ; ZÞ exp½Àb2 x1 À x Š; : f23 x; ZÞ ¼ f22 x2 ; ZÞ exp½Àb3 ... calculate F (x, Z): x x1 > f11 x; ZÞ ¼ a expðÀb1 x þ ðZ À aÞ expðÀcxÞ; > > < f12 x; ZÞ ¼ f11 x1 ; ZÞ expðÀb2 x1 À x Š; x x x2 ð74Þ F1 x; ZÞ ¼ f13 x; ZÞ ¼ f12 x2 ; ZÞ exp½Àb3 x2 À x Š; x x x3 > ... calculating S (x, Z ) has recently been proposed by Szaloki (1996): X > < s1 x; ZÞ ¼ di ½exp x À 1Ši ; x xi S x; ZÞ ¼ i¼1 > : s2 x; ZÞ ¼ ½Z À s1 x; ZÞ À t2 Šg1 x þ t2 g2 x þ s1 x1 ; ZÞ x1 < x ð66Þ...

Ngày tải lên: 10/04/2014, 18:53

Ngày tải lên: 13/05/2014, 09:20

... the absorption of X rays produces We need telescopes and detectors, sensitive to X- ray light and launched on satellites above Earth’s atmosphere, to study the X- ray universe The Chandra X- ray ... what an X ray is Unfortunately, the term X ray, so applied, refers to the piece of film illuminated by X rays Mention X- ray astronomy” to people and too often they think we send beams of X rays ... sources immediately become detectable because the accumulation of X rays gradually exceeds the random arrival of background X rays X- ray astronomy needed a satellite that imaged X- rays In the...

Ngày tải lên: 11/06/2014, 10:39