142 resultados para 2-KETO-3-DEOXYGLUCONATE KINASE


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Let f : U subset of R(2) -> R(3) be a representative of a finitely determined map germ f : (R(2), 0) -> (R(3), 0). Consider the curve obtained as the intersection of the image of the mapping f with a sufficiently small sphere s(epsilon)(2) centered at the origin in R(3), call this curve the associated doodle of the map germ f. For a large class of map germs the associated doodle has many transversal self-intersections. The topological classification of such map germs is considered from the point of view of the associated doodles. (C) 2009 Elsevier Inc. All rights reserved.

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The (2)H(d,p)(3)H and (2)H(d,n)(3)He reactions have been indirectly studied by means of the Trojan Horse Method applied to the quasi-free (2)H((3)He, p(3)H)(1)H (2)H((3)He, n(3)He)(1)H reaction at 18 MeV of beam energy. This is the first experiment where the spectator (here (1)H) has been detected in coincidence with the charged participant, avoiding the limitations of standard neutron detectors. The d - d relative energy has been measured from 1.5 MeV down to 2 keV, at center of mass angles from 40A degrees to 170A degrees. Indirect angular distributions are compared with the direct behaviour in the overlapping regions.

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Cyclization of (n)butyl glyoxylate thiosemicarbazone (HBuTSC) under reflux in the presence of Pb(OAc)(2) led to tile formation of the complex [Pb(HTz)(2)] (H(2)Tz = 3,4-dihydro-3-thioxo-1,2,4-triazin-5(2H)-one), which after recrystallization from DMSO afforded the polymer [Pb(Tz)](n), the first example of a Tz(2-) metal complex. (C) 2008 Elsevier B.V. All rights reserved.

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Complexes of the type trans-[PdX(2)(isn)(2)] {X = Cl (1), N(3) (2), SCN (3), NCO (4); isn = isonicotinamide} were synthesized and evaluated for in vitro antimycobacterial and antitumor activities. The coordination mode of the isonicotinamide and the pseudohalide ligands was inferred by IR spectroscopy. Single crystal X-ray diffraction determination on 2 showed that coordination geometry around Pd(II) is nearly square planar, with the ligands in a trans configuration. All the compounds demonstrated better in vitro activity against Mycobacterium tuberculosis than isonicotinamide and pyrazinamide. Among the complexes, compound 2 was found to be the most active with MIC of 35.89 mu M. Complexes 1-4 were also screened for their in vitro antitumor activity towards LM3 and LP07 murine cancer cell lines. (C) 2010 Elsevier Masson SAS. All rights reserved.

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The reactions of PbR(2)(OAc)(2) (R=Me, Ph) with 3-(2-thienyl)-2-sulfanylpropenoic acid (H(2)tSpa) in methanol or ethanol afforded complexes [PbR(2)(tspa)] that electrospray ionization-mass spectrometry (ESI-MS) and IR data suggest are polymeric. X-ray studies showed that [PbPh(2)(tspa)(dmso)] center dot dmso, crystallized from a solution of [PbPh(2)(tspa)] in dmso, is dimeric, and that [HQ](2)[PbPh(2)(tspa)(2)] (Q=diisopropylamine), obtained after removal of [PbPh(2)(tspa)] from a reaction including Q, contains the monomeric anion [PbPh(2)(tSpa)(2)](2-). In the solid state the lead atoms are O,S-chelated by the tspa ligands in all these products, and in the latter two have distorted octahedral coordination environments. NMR data suggest that tspa(2-) remains coordinated to PbR(2)(2+) in solution in dmso. Neither thiamine nor thiamine diphosphate reacted with PbMe(2)(NO(3))(2) in D(2)O. Prior addition of H(2)tSpa protected LLC center dot PK1 renal proximal tubule cells against PbMe(2)(NO(3))(2); thiamine had no statistically significant effect by itself, but greatly potentiated the action of H(2)tSpa. Administration of either H(2)tspa or thiamine to male albino Sprague-Dawley rats dosed 30 min previously with PbMe(2)(NO(3))(2) was associated with reduced inhibition of delta-ALAD by the organolead compound, and with lower lead levels in kidney and brain, but joint administration of both H(2)tspa and thiamine only lowered lead concentration in the kidney.

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The optical, magnetic and structural properties of Eu doped low silica calcium aluminosilicate glasses were investigated. The optical absorption coefficient presented two bands at 39 246 and 29 416 cm(-1), which were assigned respectively to the 4f(7) ((8)S(7/2)) -> 4f(6) (4F(J)) 5d (T(2g)), and 4f(7) ((8)S(7/2)) -> 4f(6) (4F(J)) 5d (E(g)) transitions of Eu(2+). The fluorescence measured at 300 K on a sample doped with 0.5 wt% of Eu(2)O(3) exhibited a broad band centered at 17 350 cm(-1), which is attributed to the 4f(6)5d -> 4f(7) transition of Eu(2+), whereas the additional peaks are due to the (5)D(0) -> (7)F(J) (J = 1, 2, 4) transitions of Eu(3+). From magnetization and XANES data it was possible to evaluate the fractions of Eu(2+) and Eu(3+) for the sample doped with 0.5 and 5.0 wt% of Eu(2)O(3), the values of which were approximately 30 and 70%, respectively.

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Hydroxymethylnitrofurazone presents in vitro activity against Trypanosoma cruzi. The optimization of the synthesis of this compound was performed through a 3(2) factorial statistical design. Quadratic model produced the best response surface predicting a maximum yield (82%) close to the center design point with a seven hours reaction and a 1:1.5 (NF:K(2)CO(3)) ratio.

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The synthesis and characterization of lanthanide(III) citrates with stoichiometries 1:1 and 2:3; [LnL center dot xH(2)O] and [Ln(2)(LH)(3)center dot 2H(2)O], Ln=La, Ce, Pr, Nd, Sm and Eu are reported. L stands for (C6O7H5)(3-) and LH for (C6O7H6)(2-). Infrared absorption spectra of both series evidence coordination of carboxylate groups through symmetric bridges or chelation. X-ray powder patterns show the amorphous character of [LnL center dot xH(2)O]. The compounds [Ln(2)LH(3)center dot 2H(2)O] are crystalline and isomorphous. Emission spectra of Eu compounds suggest C-2v symmetry for the coordination polyhedron of [LnL center dot xH(2)O] and C-4v for [Ln(2)(LH)(3)center dot 2H(2)O]. Thermal analyses (TG-DTG-DTA) were carried out for both series. The thermal analysis patterns of the two series are quite different and both fit in a 4-step model of thermal decomposition, with lanthanide oxides as final products.

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Nanosecond laser flash photolysis has been used to investigate injection and back electron transfer from the complex [(Ru-(bpy)(2)(4,4`-(PO(3)H(2))(2)bpy)](2+) surface-bound to TiO(2) (TiO(2)-Ru(II)). The measurements were conducted under conditions appropriate for water oxidation catalysis by known single-site water oxidation catalysts. Systematic variations in average lifetimes for back electron transfer, - were observed with changes in pH, surface coverage, incident excitation intensity, and applied bias. The results were qualitatively consistent with a model involving rate-limiting thermal activation of injected electrons from trap sites to the conduction band or shallow trap sites followed by site-to-site hopping and interfacial electron transfer, TiO(2)(e(-))-Ru(3+) -> TiO(2)-Ru(2+). The appearance of pH-dependent decreases in the efficiency of formation of TiO(2)-Ru(3+) and in incident-photon-to-current efficiencies with the added reductive scavenger hydroquinone point to pH-dependent back electron transfer processes on both the sub-nanosecond and millisecond-microsecond time scales, which could be significant in limiting long-term storage of multiple redox equivalents.

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The presence of paramagnetic species in the aqueous ring opening metathesis polymerizations of the exo,exo-7-oxabicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid monomer with RuCl(3) and K(2)[RuCl(5)H(2)O] compounds was studied using ESR techniques. It was observed that the intensities of the Ru(III) signals in the ESR spectra decrease on the time scale of the induction period so that the ROMP can take place. The intensity of the Ru(III) signal almost disappeared 50 min after reacting with K(2)[RuCl(5)H(2)O] and after 100 mm in the case of RuCl(3). Reactions of the cis-[Ru(NH(3))(4)(H(2)O)(2)](tfms)(3) and [Ru(NH(3))(5)H(2)O](tfms)(3) complexes with the monomer and different organic compounds representing the organic functions in the monomer (furan, norbornene, but-2-ene-1,4-diol and formic, acetic, oxalic and maleic acids) were also monitored by ESR and UV/vis spectra. It was deduced that the organic acids provide the disappearance of the Ru(III) signal. The proton NMR relaxation times of the residual water in D(2)O for reactions with oxalic acid suggested that the presence of paramagnetic ions in the solution decreases along with

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2,3-Dihydroxynaphthalene (H(2)dhn) reacts with [ReOCl(3)-(PPh(3))(2)] or [ReOBr(3)(PPh(3))(2)] in a 1:1 molar ratio with formation of the isostructural complexes [ReOCl(2)(PPh(3))(2)(Hdhn)] (4) and [ReOBr(2)-(PPh(3))(2)(Hdhn)] (5). They have distorted octahedral coordination spheres with the halide and the triphenylphosphine ligands arranged in equatorial trans positions to each other. The Hdhn-ligand coordinates monodentately in trans position to the oxo ligand. Intramolecular hydrogen bonds between the Hdhn and the halogeno ligands stabilize this coordination mode. The products represent the first examples of oxorhenium(V) complexes with monodentate catecholate-type ligands.

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The evolution of internal stresses in oxide scales growing on polycrystalline Fe(3)Al alloy in atmospheric air at 700 degrees C was determined using in situ energy-dispersive synchrotron X-ray diffraction. Ex situ texture analyses were performed after 5 h of oxidation at 700 degrees C. Under these conditions, the oxide-scale thickness, as determined by X-ray photoelectron spectroscopy, lies between 80 and 100 nm. The main phase present in the oxide scales is alpha-Al(2)O(3), with minor quantities of metastable theta-Al(2)O(3) detected in the first minutes of oxidation, as well as alpha-Fe(2)O(3). alpha-Al(2)O(3) grows with a weak (0001) fiber texture in the normal direction. During the initial stages of oxidation the scale develops, increasing levels of compressive stresses which later evolve to a steady state condition situated around -300 MPa. (C) 2010 International Centre for Diffraction Data. [DOI: 10.1154/1.3402764]

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In the title salt, K(+)center dot C(4)H(7)BF(3)O(-), the K atom is surrounded by six anions making close contacts through seven F [K center dot center dot center dot F = 2.779 (1)-3.048 (1) angstrom] and two O [K center dot center dot center dot O = 2.953 (2) and 3.127 (2) angstrom] atoms in a trivacant fac-vIC-9 icosahedral coordination geometry.

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The prevalence of human T-cell lymphotropic viruses types 1 and 2 (HTLV-1/2) in Mozambique is not known. The present study examined blood samples from 208, 226, and 318 individuals from Northern, Central, and Southern Mozambique, respectively, of all socioeconomic and demographic strata attending public health centers in Mozambique for HTLV-1/2-specific antibodies. Serum samples were assessed for HIV- and HTLV-1/2-specific antibodies by using enzyme immunoassays, and infections with HTLV-1 and -2 were confirmed by using Western blot. An overall HTLV-1/2 prevalence of 2.3% (2.9% in female and 1.1% in male subjects) was observed, and the prevalence of infection increased with age. Regional variation in the prevalence of HIV and HTLV-1/2 was observed; 32.2%, 65.5%, and 44% of individuals tested HIV positive in Northern, Central, and Southern Mozambique, respectively, and 2.4%, 3.9%, and 0.9% tested HTLV-1/2 positive in the same regions. HTLV-1 infection was confirmed in these individuals. No association between HTLV-1 infection and socio-demographic variables or HIV status was detected, although the low number of HTLV-1-positive cases did not allow robust statistical analyses. The results obtained suggest different risk factors and epidemiologic correlates of HIV and HTLV-1 transmission in Mozambique. Furthermore, our results suggested that North and Central Mozambique should be considered endemic regions for HTLV-1 infection. As no cases of HTLV-2 were detected, HTLV-2 appears to have not been introduced into Mozambique.

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Dengue viruses (DENV) serotypes 1, 2, and 3 have been causing yearly outbreaks in Brazil. In this study, we report the reintroduction of DENV2 in the coast of Sao Paulo State. Partial envelope viral genes were sequenced from eighteen patients with dengue fever during the 2010 epidemic. Phylogenetic analysis showed this strain belongs to the American/Asian genotype and was closely related to the virus that circulated in Rio de Janeiro in 2007 and 2008. The phylogeny also showed no clustering by clinical presentation, suggesting that the disease severity could not be explained by distinct variants or genotypes. The time of the most recent common ancestor of American/Asian genotype and the Sao Paulo and Rio de Janeiro (SP/RJ) monophyletic cluster was estimated to be around 40 and 10 years, respectively. Since this virus was first identified in Brazil in 2007, we suggest that it was already circulating in the country before causing the first documented outbreak. This is the first description of the 2010 outbreak in the State of Sao Paulo, Brazil, and should contribute to efforts to control and monitor the spread of DENVs in endemic areas.