Low molecular weight proteins in urines from healthy subjects as well as diabetic,nephropathic and diabetic‐nephropathic patients: a MALDI study

Urine samples from healthy subjects as well as diabetic, nephropathic and diabetic‐nephropathic patients were analyzed by matrix assisted laser desorption/ionization (MALDI) mass spectrometry in order to establish evidence of some possible differences in the peptide profile related to the pathological states. Multivariate analysis suggested the possibility of a distinction among the considered groups of patients. Some differences have been found, in particular, in the relative abundances of three ions at m/z 1912, 1219 and 2049. For these reasons, further investigation was carried out by MALDI/TOF/TOF to determine the sequence of these peptides and, consequently, to individuate their possible origin. By this approach, the peptide at m/z 1912 was found to originate from uromodulin, and its lower expression in the case of nephropathy can be well related to the pathological condition. Ions at m/z 2049 and 1219 originate from the collagen α‐1(I) chain precursor and from the collagen α‐5 (IV) chain precursor, respectively, and, also in this case, their different expressions can be related to the pathologies under investigation. The obtained data seem to indicate that urine is an interesting biological fluid to investigate on the peptide profile and to obtain, consequently, information on the dismetabolism activated by specific pathologies. Copyright © 2009 John Wiley & Sons, Ltd.     

Radical salts of bis(ethylenediseleno)tetrathiafulvalene with paramagnetic tris(oxalato)metalate anions

The synthesis, crystal structure, and physical characterization of five new radical salts formed by the organic donor bis(ethylenediseleno)tetrathiafulvalene (BEST) and the paramagnetic tris(oxalato)metalate anions [M(C2O4)3]3- (M = FeIII and CrIII) are reported. The salts isolated are (BEST)4[M(C2O4)3].PhCOOH.H2O with MIII = Cr (1) or Fe (2) (crystal data: 1, triclinic, space group P(-)1 with a = 14.0999(4) A, b = 15.3464(4) A, c =19.5000(4) A, alpha = 76.711(5) degrees, beta = 71.688(5) degrees, gamma = 88.545(5) degrees, V = 3893.5(2) A3, and Z = 2; 2, triclinic, space group P(-)1 with a = 14.0326(3) A, b =15.1981(4) A, c =19.4106(4) A, alpha = 76.739(5) degrees, beta = 71.938(5) degrees, gamma = 88.845(5) degrees, V = 3824.9(2) A3, and Z = 2), (BEST)4[M(C2O4)3].1.5H2O with MIII = Cr (3) or Fe (4) (crystal data: 3, monoclinic, space group C2/m with a = 33.7480(10) A, b =12.3151(7) A, c = 8.8218(5) A, beta = 99.674(5) degrees, V = 3614.3(3) A3, and Z = 2; 4, monoclinic, space group C2/m with a = 33.659(6) A, b =12.248(2) A, c = 8.759(2) A, beta = 99.74(3) degrees, V = 3558.9(12) A3, and Z = 2), and (BEST)9[Fe(C2O4)3]2.7H2O (5) (crystal data: triclinic, space group P(-)1 with a =12.6993(3) A, b =18.7564(4) A, c = 18.7675(4) A, alpha = 75.649(5) degrees, beta = 107.178(5) degrees, gamma = 79.527(5) degrees, V = 3977.5(3) A3, and Z = 1). The structures of all these salts consist of alternating layers of the organic donors and tris(oxalato)metalate anions. In 1 and 2 the anionic layers contain also benzoic acid molecules H-bonded to the terminal oxygen atoms of the anions. In all salts the organic layers adopt beta-type packings. Along the parallel stacks the donors form dimers in 3 and 4, trimers in 5, and tetramers in 1 and 2. All the compounds are paramagnetic semiconductors with high room-temperature conductivities and magnetic susceptibilities dominated by the Fe- or Cr-containing anions.     

Synthesis and characterization of a soluble bimetallic oxalate-based bidimensional magnet: [K(18-crown-6)]3[Mn3(H2O)4{Cr(ox)3}3

The "templating" K crown ether cation allows for the preparation of soluble layered oxalate-based bimetallic magnets, as in [K(18-crown-6]3{Mn3(H2O)4[Cr(ox)3]3}, with an unprecedented bidimensional polymeric anionic network that involves both oxalato bridges and H bonds. As in other 2D oxalate-bridged compounds, the compound behaves as a soft ferromagnet, with the onset of magnetic ordering occurring at 3.3 K.     

Spectroscopic and potentiometric characterization of oxovanadium(IV) complexes formed by 3-hydroxy-4-pyridinones. Rationalization of the influence of basicity and electronic structure of the ligand on the properties of V(IV)O species in aqueous solution

Aqueous solution studies regarding the identification and characterization of complexes formed by the VIVO ion and 11 3-hydroxy-4-pyridinone derivatives have been performed using EPR and UV/vis spectroscopic techniques. For the three ligands (HL) adequately soluble in water (1-methyl-3-hydroxy-4-pyridinone, 1-methyl-2-ethyl-3-hydroxy-4-pyridinone, and 1,2-diethyl-3-hydroxy-4-pyridinone), potentiometric titrations were performed; the results are consistent with the formation of [V(IV)OL]+, [V(IV)OL2], [V(IV)OL2H(-1)]-, [(V(IV)O)2L2H(-2)], and [V(IV)L3]+ species. Bis chelated complexes are characterized by a cis-trans isomerism, the trans isomer being strongly favored with respect to the cis arrangement. Tris chelated non-oxo V(IV) species were prepared in CH3COOH; their spectroscopic features point to a d(z2) ground state and a geometry intermediate between an octahedron and a trigonal prism, related to the steric requirements of the substituent on the carbon atom in position 2 of the pyridinone ring. Four new solid derivatives, [V(IV)O(1,2-diethyl-3-hydroxy-4-pyridinonato)2], [V(IV)O(1-(p-tolyl)-2-ethyl-3-hydroxy-4-pyridinonato)2], [V(IV)O(1-(p-(n-butyl)phenyl)-2-ethyl-3-hydroxy-4-pyridinonato)2], and [V(IV)O(1-(p-(n-hexyl)phenyl)-2-ethyl-3-hydroxy-4-pyridinonato)2], were isolated and characterized; they exhibited a five-coordinate geometry close to square-pyramid. A criterion for establishing the degree of distortion toward the trigonal-bipyramid on the basis of the electronic absorption spectra is provided. Relationships between the pKa of the -OH group in position 3 of the ring and (i) log K of mono and bis chelated complexes, (ii) pK of the water molecule in cis-[V(IV)OL2(H2O)], (iii) log K of tris chelated species [V(IV)L3]+, and (iv) 51V hyperfine coupling constant (Az) have been established and discussed for a number of pyrone, pyridinone, and catechol ligands. The results are rationalized by assuming for pyridinones an electronic structure intermediate between that of pyrones and catechols. The relationships are valuable to the understanding of the behavior of VIVO species in aqueous solution.     

Synthesis and anti-HIV activity of novel cyclopentenyl nucleoside analogues of 8-azapurine

Novel nucleoside analogues of structure 3-5 were synthesized starting from (+/-)-cis-2-amino-3-cyclopentenylmethanol (1). The chlorine derivative 3 inhibited both HIV-1 and HIV-2 replication in MT-4 cells with IC(50) values of 10.67 microM and of 13.79 microM, respectively.     

Multivariate analysis approach to the plasma protein profile of patients with advanced colorectal cancer

The aim of the present study was to identify the pattern of plasma protein species of interest as markers of colorectal cancer (CRC). Using matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS), the plasma protein profile was determined in nine stage IV CRC patients (study group) and nine clean-colon healthy subjects (control group). Multivariate analysis methods were employed to identify distinctive disease patterns at protein spectrum. In the study and control groups, cluster analysis (CA) on the complete MALDI-MS spectra plasma protein profile showed a distinction between CRC patients and healthy subjects, thus allowing the identification of the most discriminating ionic species. Principal component analysis (PCA) and linear discriminant analysis (LDA) yielded similar grouping results. LDA with leave-one-out cross validation achieved a correct classification rate of 89% in both the patients and the healthy subjects.     

Stable single-layer light-emitting electrochemical cell using 4,7-diphenyl-1,10-phenanthroline-bis(2-phenylpyridine)iridium(III) hexafluorophosphate

A significant improvement in the stability of a light emitting electrochemical cell was achieved by utilizing a novel iridium(III) complex: 4,7-diphenyl-1,10-phenanthroline-bis(2-phenylpyridine)iridium(III) hexafluorophosphate. The enhanced device stability is correlated by means of DFT studies to be related to a more efficient shielding of the reactive LUMO of the complex.     

Parametrization of the magnetic behavior of the triangular spin ladder chains organically templated: (C2N2H10)[M(HPO3)F3] (M(III) = Fe, Cr, and V). Crystal structure and thermal and spectroscopic properties of the iron(III) phase

A new iron(III) phosphite templated by ethylenediamine has been synthesized using solvothermal conditions under autogenous pressure. The (C2N2H10)[Fe(HPO3)F3] compound has been characterized by single-crystal X-ray diffraction data and spectroscopic and magnetic techniques. The crystal structure is formed by chains extended along the c axis and surrounded by ethylenediammonium cations. A study by diffuse-reflectance spectroscopy has been performed, and the calculated Dq, B, and C parameters for the Fe(III) cations are 1030, 720, and 3080 cm(-1), respectively. The M?ssbauer spectrum at room temperature is characteristic of Fe(III) ions. The electron spin resonance (ESR) spectra carried out at different temperatures show isotropic signals with a g value of 2.00(1). The thermal evolution of the intensity of the ESR signals indicates the existence of antiferromagnetic interactions for the Fe(III) phase. The magnetic susceptibility data of the Cr(III) and V(III) compounds show antiferromagnetic couplings. The J-exchange parameters of the Fe(III) and Cr(III) compounds have been calculated by using a model for a triangular spin ladder chain. The values are J1 = -1.63(1) K and J2 = -0.87(2) K with g = 2.02 for the Fe(III) phase and J(1) = -0.56(2) K and J2 = -0.40(2) K with g = 1.99 for the Cr(III) compound. In the case of the V(III) phase, the fit has been performed considering a linear chain with the magnetic parameters D = 2.5 cm(-1) and J = -1.15(1) K.     

Photorefractive solitons embedded in gratings in centrosymmetric crystals

We investigate (1+1D) spatial optical solitons embedded in a fixed-volume grating in centrosymmetric photorefractive crystals. We numerically identify a two-parameter soliton family and deduce both its existence surface and soliton profiles. For shallow gratings, the soliton Fourier spectrum exhibits three lobes located at the reciprocal lattice points -K, 0, and K. Soliton trapping is a consequence of both the self-induced nonlinear waveguide and the grating reflectivity, which prevents the breakaway of the lateral components. To provide a preliminary evaluation of soliton stability, we also investigate the propagation of slightly perturbed soliton profiles.