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Re-accreditation consists in certifying the renewal of specific competencies of qualified professionals as mentioned in the health profession management law. The objective is to certify that the professional is qualified to perform a professional exercise in order to guarantee quality healthcare. The professional bodies and scientific societies should contribute by facilitating the continuing professional development, and the Health Administration should be responsible for guaranteeing the whole process.

International audience; Herein we report a detailed investigation of the complexation properties of the macrocyclic decadentate receptor N,N'-Bis[(6-carboxy-2-pyridil)methyl]-4,13-diaza-18-crown-6 (H(2)bp18c6) toward different divalent metal ions [Zn(II), Cd(II), Pb(II), Sr(II), and Ca(II)] in aqueous solution. We have found that this ligand is especially suited for the complexation of large metal ions such as Sr(II) and Pb(II), which results in very high Pb(II)/Ca(II) and Pb(II)/Zn(II) selectivities (in fact, higher than those found for ligands widely used for the treatment of lead poisoning such as ethylenediaminetetraacetic acid (edta)), as well as in the highest Sr(II)/Ca(II) selectivity reported so far. These results have been rationalized on the basis of the structure of the complexes. X-ray crystal diffraction, (1)H and (13)C NMR spectroscopy, as well as theoretical calculations at the density functional theory (B3LYP) level have been performed. Our results indicate that for large metal ions such as Pb(II) and Sr(II) the most stable conformation is Delta(delta lambda delta)(delta lambda delta), while for Ca(II) our calculations predict the Delta(lambda delta lambda)(lambda delta lambda) form being the most stable one. The selectivity that bp18c6(2-) shows for Sr(II) over Ca(II) can be attributed to a better fit between the large Sr(II) ions and the relatively large crown fragment of the ligand. The X-ray crystal structure of the Pb(II) complex shows that the Delta(delta lambda delta)(delta lambda delta) conformation observed in solution is also maintained in the solid state. The Pb(II) ion is endocyclically coordinated, being directly bound to the 10 donor atoms of the ligand. The bond distances to the donor atoms of the pendant arms (2.55-2.60 angstrom) are substantially shorter than those between the metal ion and the donor atoms of the crown moiety (2.92-3.04 angstrom). This is a typical situation observed for the so-called hemidirected compounds, in which the Pb(II) lone pair is stereochemically active. The X-ray structures of the Zn(II) and Cd(II) complexes show that these metal ions are exocyclically coordinated by the ligand, which explains the high Pb(II)/Cd(II) and Pb(II)/Zn(II) selectivities. Our receptor bp18c6(2-) shows promise for application in chelation treatment of metal intoxication by Pb(II) and (90)Sr(II).

[Abstract] The coordinative properties towards lead(II) of two lateral macrobicyclic receptors that incorporate either a 1,10‐diaza‐[15]crown‐5 (L7) or a 4,13‐diaza‐[18]crown‐6 (L8) fragment are reported. Spectrophotometric titrations performed in acetonitrile solution indicate only the formation of mononuclear complexes in solution. The X‐ray crystal structures of the two receptors show that the conformation adopted by the ligand is imposed by the presence of intramolecular hydrogen‐bonding interactions that involve the secondary amine groups and the pivotal nitrogen atoms. The solid‐state structure of [Pb(L7)(NCS)](SCN)·0.5H2O shows that the metal ion is asymmetrically coordinated inside the macrobicyclic cavity. The PbII ion is coordinated to the nitrogen atom of the pyridine unit, the two secondary amine atoms, two oxygen atoms of the crown moiety, and a nitrogen atom of an isothiocyanate group. The distances between the PbII ion and the two pivotal nitrogen atoms as well as one of the oxygen atoms of the crown moiety are too long (>2.92 Å) to be considered unequivocal bonds, and should be regarded only as weak interactions. The protonation constants of L7 and L8 as well as the stability constants of their PbII complexes were investigated by using potentiometric titrations in 95 % methanol (I = 0.1 M, nBu4NClO4, 25 °C). The two receptors undergo two protonation processes in the pH range investigated (2.0 < pH < 12.0), which correspond to the protonation of the nitrogen atoms of the oxa–aza moiety. The log KPbL value obtained for L7 [9.906(1)] is approximately 1.1 log K units higher than the one determined for L8 [8.75(1)]. Xunta de Galicia; PGIDIT06TAM10301PR Xunta de Galicia; INCITE09E1R103013ES

The cri du chat syndrome (CDCS) come from a partial or total deletion of the short arm of chromosome 5, being one of the most common deletion syndromes in human beings. The great majority of patients are diagnosed between the first month and first year of life, but herein we report a finding of a CDCS in a woman with a suspect of spinocerebellar ataxia, and a family medical record of ataxia and bipolar disorder. We pay special attention to the clinical features as well as the diagnostics tests, used to identify the CDCS.We report a case of a 46 years-old woman showing a borderline intelligence and bilateral cataract surgery at the age of 43. Beginning of symptoms in childhood included hypoacusia, ataxia, dysarthria, dysphagia, depression, cognitive impairment and bipolar disorder. Physical examination showed microcephaly, micrognathia, talipes equinovarus and ataxia. Karyotype and array-CGH were carried out on peripheral blood. The patient showed a rearrangement involving chromosomes 5 and 15, as well as an inversion of chromosome 9: 45,XX,inv9(p11q13);t(5,15)(p15.33;q11.2). Array comparative genomic hybridization was performed showing a 2.91 Mb deletion at 5p15.33, genomic formula arr 5p15.33 (151537-3057771)x1. The deletion involved 20 genes, including TERT gene.The multiple gene deletions confirmed the CDCS diagnosis, being responsible for the patient phenotype. It has been showed up the importance of using the correct diagnosis techniques (array-CGH, peripheral blood karyotype) as well as their appropriate choice.Hallazgo inesperado de sindrome cri du chat en una paciente adulta mediante array-CGH.Introduccion. El sindrome cri du chat (SCDC) tiene su origen en una delecion parcial o total del brazo corto del cromosoma 5, y es uno de los sindromes de delecion cromosomica mas frecuentes en humanos. La mayoria de los pacientes se diagnostica entre el primer mes y el primer año de vida, si bien aqui se describe el hallazgo de un SCDC en una mujer con sospecha de ataxia espinocerebelar y antecedentes familiares de trastorno bipolar y ataxia, con especial atencion a las caracteristicas clinicas y las tecnicas diagnosticas que permitieron su identificacion. Caso clinico. Mujer de 46 años que presentaba una inteligencia limite, intervenida a los 43 años de faquectomia bilateral. El inicio de la sintomatologia fue durante la infancia, e incluia hipoacusia, ataxia, disartria, disfagia, depresion, deterioro cognitivo y trastorno bipolar. La exploracion fisica revelo microcefalia, micrognatia, pies equinos y ataxia. Se realizo cariotipo y array-CGH en sangre periferica. La paciente presentaba una traslocacion que involucraba los cromosomas 5 y 15, y una inversion del cromosoma 9: 45,XX,inv9(p11q13);t(5,15)(p15.33;q11.2). El array-CGH mostro una delecion de 2,91 Mb en 5p15.33, formula genomica arr 5p15.33 (151537-3057771)x1, que involucraba 20 genes, incluyendo el gen TERT. Conclusiones. La delecion de multiples genes confirmo el diagnostico de SCDC y es la responsable del fenotipo de la paciente. Se pone de manifiesto la importancia de utilizar tecnicas adecuadas de diagnostico (array-CGH, cariotipo en sangre periferica) y la correcta eleccion de estas.

[Abstract] Herein we report on the macrocyclic receptor N,N′‐bis[(6‐carboxy‐2‐pyridyl)methyl]‐1,10‐diaza‐15‐crown‐5 (H2bp15c5) and its coordination properties towards ZnII, CdII, PbII, and CaII. The stability constants of these complexes determined by pH‐potentiometric titration at 25 °C in 0.1 M KNO3 vary in the following order: PbII > CdII >> ZnII > CaII. As a result, bp15c5 presents very important PbII/ZnII and PbII/CaII selectivities. These results are in contrast to those reported for the related receptor derived from 1,7‐diaza‐12‐crown‐4, which provides very similar complex stabilities for ZnII and PbII. The X‐ray crystal structure of [Cd(Hbp15c5)]+ shows heptadentate binding of the ligand to the metal ion, with two oxygen atoms of the macrocyclic unit remaining uncoordinated. The 1H NMR spectra of the complexes formed with PbII, ZnII, and CaII (D2O) show very broad peaks in the region 2–5 ppm, indicating an important degree of flexibility of the crownmoiety in these complexes. On the contrary, the 1H and 13C NMR spectra recorded for the CdII complex are well resolved and could be fully assigned. A detailed conformational investigation using theoretical calculations performed at the DFT (B3LYP) level predict a minimum energy conformation for [Cd(bp15c5)] that is very similar to that observed in the solid state. Analogous calculations performed on the [M(bp15c5)] (M = Zn or Pb) systems predict hexadentate binding of the ligand to these metal ions. In the case of the PbII complex our calculations indicate that the 6s lone pair is stereochemically active, which results in a hemidirected coordination geometry around the metal ion. The minimum energy conformations calculated for the ZnII, CdII, and PbII complexes are compatible with the experimental NMR spectra obtained in D2O solution. Xunta de Galicia; PGIDIT06TAM10301PR Xunta de Galicia; INCITE09E1R103013ES

The thermodynamic stability of the Pb(II), Cd(II), Zn(II), and Ca(II) complexes with the dianionic macrocyclic ligand N,N'-bis[(6-carboxy-2-pyridyl)methyl]-1,7-diaza-12-crown-4 (H(2)bp12c4) has been investigated by pH-potentiometric titrations at 25 degrees C in 0.1 M KNO(3). The stability constants vary in the following order: Cd(II)Zn(II) approximately Pb(II)Ca(II). As a consequence, H(2)bp12c4 present an important Cd(II)/Ca(II) selectivity, as well as a certain selectivity for Cd(II) over Zn(II). To rationalize these results, a detailed investigation of the structure of these complexes has been carried out both in solid state and in aqueous solution. Furthermore, the [M(bp12c4)] complexes (M = Ca, Zn, Cd, or Pb) were characterized by means of density functional theory (DFT) calculations (B3LYP model) to obtain information on their solution structures and to investigate the possible stereochemical activity of the Pb(II) lone pair. Our results show that in all cases the metal ion is octacoordinated by the ligand, a situation that is particularly rare for Zn(II) complexes. The coordination polyhedra observed in the solid state for the [M(bp12c4)] complexes (M = Zn, Cd, or Ca) is closely related to the conformation adopted by the ligand in the corresponding complex: The Zn(II) complex adopts a Delta(lambdalambdalambdalambda) conformation in the solid state, which results in a square antiprismatic coordination, while the Delta(deltadeltadeltadelta) conformation observed for the Cd(II) and Ca(II) analogues yields inverted-square antiprismatic geometries. The X-ray crystal structure of the Pb(II) analogue shows that the metal ion is directly bound to the eight donor atoms of the ligand, but the bond distances of the metal coordination environment indicate an asymmetrical coordination of the cation by the ligand, which is attributed to the stereochemical activity of the Pb(II) lone pair. In aqueous solution the Ca(II), Zn(II), and Cd(II) complexes show rigid C(2) symmetries, while the Pb(II) analogue presents a more flexible structure.

Introduccion. El sindrome cri du chat (SCDC) tiene su origen en una delecion parcial o total del brazo corto del cromosoma 5, y es uno de los sindromes de delecion cromosomica mas frecuentes en humanos. La mayoria de los pacientes se diagnostica entre el primer mes y el primer ano de vida, si bien aqui se describe el hallazgo de un SCDC en una mujer con sospecha de ataxia espinocerebelar y antecedentes familiares de trastorno bipolar y ataxia, con especial atencion a las caracteristicas clinicas y las tecnicas diagnosticas que permitieron su identificacion. Caso clinico. Mujer de 46 anos que presentaba una inteligencia limite, intervenida a los 43 anos de faquectomia bilateral. El inicio de la sintomatologia fue durante la infancia, e incluia hipoacusia, ataxia, disartria, disfagia, depresion, deterioro cognitivo y trastorno bipolar. La exploracion fisica revelo microcefalia, micrognatia, pies equinos y ataxia. Se realizo cariotipo y array-CGH en sangre periferica. La paciente presentaba una traslocacion que involucraba los cromosomas 5 y 15, y una inversion del cromosoma 9: 45,XX,inv9(p11q13);t(5,15)(p15.33;q11.2). El array-CGH mostro una delecion de 2,91 Mb en 5p15.33, formula genomica arr 5p15.33 (151537-3057771)x1, que involucraba 20 genes, incluyendo el gen TERT. Conclusiones. La delecion de multiples genes confirmo el diagnostico de SCDC y es la responsable del fenotipo de la paciente. Se pone de manifiesto la importancia de utilizar tecnicas adecuadas de diagnostico (array-CGH, cariotipo en sangre periferica) y la correcta eleccion de estas.

[Abstract] Herein, we report the coordination properties towards Zn(II), Cd(II) and Pb(II) of two hexadentate ligands containing pyridinecarboxylate groups with ethane-1,2-diamine (bcpe) or cyclohexane-1,2-diamine (bcpc) backbones. The X-ray crystal structures of [Zn(bcpe)], [Cd(bcpe)] and [Cd(bcpc)] show hexadentate binding of the ligand to the metal ions, with the coordination polyhedron being best described as a severely distorted octahedron. The X-ray crystal structure of the Pb(II) analogue shows the presence of tetrameric structural units [Pb4(bcpe)4] in which the four Pb(II) ions are bridged by carboxylate oxygen atoms. While in the Zn(II) and Cd(II) complexes the bcpe ligand adopts a twist–wrap (tw) conformation in which the ligand wraps around the metal ion by twisting the pyridyl units relative to each other, for the Pb(II) complex a twist–fold (tf) conformation, where a slight twisting of the pyridyl units is accompanied by an overall folding of the two pyridine units relative to each other is observed. Theoretical calculations performed at the DFT (B3LYP) level on the [Pb(bcpe)] and [Pb(bcpc)] systems indicate that the tf conformation is more stable than the tw form both in the solid state and in aqueous solution. The analysis of the natural bond orbitals (NBOs) indicate that the Pb(II) lone-pair is polarized by a substantial 6p contribution, which results in a hemi-directed coordination geometry around the metal ion. Potentiometric studies have been carried out to determine the protonation constants of the ligands and the stability constants of the complexes with Zn(II), Cd(II), Pb(II) and Ca(II). The replacement of the ethylene backbone of bcpe by a cyclohexylene ring causes a very important increase in the stability constant of the Pb(II) complex (ca. 2.3 logK units), while this effect is less important for Cd(II) (ca. 1.4 logK units). However, the introduction of the cyclohexylene ring does not substantially affect the stability of the Zn(II) and Ca(II) complexes. The ligand bcpc shows Pb/Ca and Cd/Ca selectivities [108.9 and 109.8, respectively] superior to those of extracting agents, such as EDTA, already used in Pb(II) and Cd(II) removal from contaminated water and soils. Galicia. Consellería de Innovación, Industria e Comercio; PGIDIT06TAM10301PR