RESUMEN
In order to obtain the structural and electronic properties of pristine copper clusters and Cu13-SF6, Cu43-SF6, Cu55-SF6, Cu13-2SF6, Cu43-2SF6, and Cu55-2SF6 systems, DFT calculations were carried out. For Cu13-mSF6, its surface suffers a drastic deformation, and Cu43-mSF6 at its outer surface reveals strong interaction for the first chemical molecule; when the second molecule is interacting, these outer surfaces are not severely affected. These two cases degraded fully the first SF6 molecule; however the second molecule is bonded to the latter systems and for Cu55-mSF6 (m = 1 and 2) a structural transformation from SF6 âSF4 appears as well as inner and outer shells that display slight deformations. The electronic gaps do not exhibit drastic changes after adsorption of mSF6 molecules, and the magnetic moment remains without alterations. The whole system shows thermal and vibrational stability. In addition, for Cu13-mSF6 the values of the optical gap and intensity of the optical exhibit changes with respect to the pristine case (Cu13), and the rest of the systems do not exhibit major oscillations. These icosahedral copper clusters emerge as a good option to degrade mSF6 molecules.
RESUMEN
[This corrects the article DOI: 10.1155/2013/524701.].
RESUMEN
The palladium(II) bis-chelate complexes of the type [Pd(TSC(1-5))2] (6-10), with their corresponding ligands 4-phenyl-1-(acetone)-thiosemicarbazone, HTSC(1) (1), 4-phenyl-1-(2'-chloro-benzaldehyde)-thiosemicarbazone, HTSC(2) (2), 4-phenyl-1-(3'-hydroxy-benzaldehyde)-thiosemicarbazone, HTSC(3) (3), 4-phenyl-1-(2'-naphthaldehyde)-thiosemicarbazone, HTSC(4) (4), and 4-phenyl-1-(1'-nitro-2'-naphthaldehyde)-thiosemicarbazone, HTSC(5) (5), were synthesized and characterized by elemental analysis and spectroscopic techniques (IR and (1)H- and (13)C-NMR). The molecular structure of HTSC(3), HTSC(4), and [Pd(TSC(1))2] (6) have been determined by single crystal X-ray crystallography. Complex 6 shows a square planar geometry with two deprotonated ligands coordinated to Pd(II) through the azomethine nitrogen and thione sulfur atoms in a cis arrangement. The in vitro cytotoxic activity measurements indicate that the palladium(II) complexes (IC50 = 0.01-9.87 µM) exhibited higher antiproliferative activity than their free ligands (IC50 = 23.48-70.86 and >250 µM) against different types of human tumor cell lines. Among all the studied palladium(II) complexes, the [Pd(TSC(3))2] (8) complex exhibited high antitumor activity on the DU145 prostate carcinoma and K562 chronic myelogenous leukemia cells, with low values of the inhibitory concentration (0.01 and 0.02 µM, resp.).
RESUMEN
The copper (II) complexes (CuL(2)) were prepared by reaction of Cu(CH(3)COO)(2) with the corresponding derivatives of acylthioureas in a Cu:HL molar ratio of 1:2. Acylthiourea ligands, N,N-diethyl-N'-(R-benzoyl) thiourea (HL(1-3)) [R=H, o-Cl and p-NO(2)] were synthesized in high yield (78-83%) and characterized by elemental analysis, infrared spectroscopy, (1)H and (13)C NMR spectroscopy. The complexes CuL(2) were characterized by elemental analysis, IR, FAB(+)-MS, magnetic susceptibility measurements, EPR and cyclic voltammetry. The crystal structure of the complex Cu(L(2))(2) shows a nearly square-planar geometry with two deprotonated ligands (L) coordinated to Cu(II) through the oxygen and sulfur atoms in a cis arrangement. The antitumor activity of the copper(II) complexes with acylthiourea ligands was evaluated in vitro against the mouse mammary adenocarcinoma TA3 cell line. These complexes exhibited much higher cytotoxic activity (IC(50) values in the range of 3.9-6.9 muM) than their corresponding ligands (40-240 muM), which indicates that the coordination of the chelate ligands around the Cu(II) enhances the antitumor activity and, furthermore, this result confirmed that the participation of the nitro and chloro substituent groups in the complex activities is slightly relevant. The high accumulation of the complexes Cu(L(2))(2) and Cu(L(3))(2) in TA3 tumor cells and the much faster binding to cellular DNA than Cu(L(1))(2) are consistent with the in vitro cytotoxic activities found for these copper complexes.
RESUMEN
Objetivo: Evaluar la frecuencia de presentación, características y evolución de la diabetes tipo 2 en niños y adolescentes atendidos en la Unidad de Diabetes del Servicio de Endocrinología del Hospital de Niños J. M. de Los Ríos. Métodos: Se revisaron los registros de 411 pacientes diabéticos atendidos desde Enero de 1987 hasta el primer cuatrimestre del año 2003, 16 reunieron criterios de diabetes tipo 2. Resultados: Se observó un aumento de la frecuencia de diabetes tipo 2 de 1-2% en el primer cuatrienio a 7.3% en el último. El sexo predominante fue el femenino (62.5%); un alto porcentaje (37.5%) tenía menos de 10 años de edad; el 37.5% se encontraba en Tanner II-IV de desarrollo puberal, y un porcentaje igual eran prepuberales; el 68.8% tuvo un peso normal al nacer; todos tenían antecedentes familiares de diabetes tipo 2; el 50% consultó por hallazgo incidental de hiperglicemia en ayunas; el 37.5% estaban asintomáticos al momento del diagnóstico; el 31.3% tenía acantosis y el 50% presentó exceso de peso. El 56,25% no requirió tratamiento farmacológico. Conclusión: La diabetes tipo 2 en niños y adolescentes es una entidad cada vez más frecuente en nuestra Unidad de Diabetes, lo que nos debe alertar a tenerla presente para así hacer diagnósticos precoces, y más importante aún, intervenir en la prevención de la misma.
Objective: The goal of this study, was to assess the frequency, characteristics and evolution of type 2 diabetes in children and adolescents of the Endocrinology Department of J. M. de Los Ríos Childrens Hospital, Diabetes Unit. Methods: From 411 patients that were attended since January 1987 to April 2003, 16 accomplished the inclusion criteria. Results: During the study, we found an increased frequency of type 2 diabetes from 1-2% to 7.3% in the last four-year period. Female sex was predominant (62.5%); a high percentage (37.5%) of the patients were less than ten years old; 37.5% had a pubertal development in Tanner II-IV, and the same number was prepubertal. Most of them, had normal weight at birth. All patients had a family history of type 2 diabetes in first- or second-degree relatives. Fifty percent consulted due to an incidental finding of fasting hyperglycemia; Thirty seven percent (37.5%) were asymptomatic at the diagnosis; Thirty one percent (31.3%) had acanthosis and 50% were overweight or obese. The majority of patients did not need pharmacologic treatment. Conclusion: Type 2 diabetes in children and adolescents is increasing in our Diabetes Unit. We have to be alert to do prevention in high-risk groups, encouraging them to make lifestyle changes and an early diagnosis.
RESUMEN
A low-molecular weight chromium-containing fraction of the material resulting from dichromate reduction by bovine liver homogenate was investigated by NMR and ES-MS. The ES-MS spectrum showed a readily detectable peak at m/z 786.1. The same molecular weight reasonably agreed with the relatively low diffusion coefficient measured by NMR-DOSY experiments on the main species observed in the (1)H NMR spectrum. At least two downfield shifted and broad paramagnetic signals were apparent in the (1)H NMR spectrum. Temperature dependence of chemical shift was exploited in order to estimate the diamagnetic shift of the signals in the diamagnetic region of the spectrum. 2D TOCSY, NOESY, COSY and (1)H-(13)C HMQC spectra revealed the presence of aromatic protons (which were assigned as His residues), Gly and some other short chain amino-acids. Combinations of the molecular masses of such components together with acetate (which is present in the solution) and chromium atoms allowed a tentative proposal of a model for the compound.