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1.
Transplant Proc ; 49(1): 169-171, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28104128

RESUMO

The combined liver-kidney transplantation (cLKT) is the procedure of choice for patients with end-stage liver and kidney disease. In cLKT we can usually accommodate the grafts in two different ways, varying the kidney placement. The retroperitoneal kidney implant has some advantages, such as the easy access or avoiding vascular complications. We propose a new single incision, not yet reported, maintaining an extraperitoneal kidney, with excellent surgical field for cLKT and possible reduction of the impact of wound complications.


Assuntos
Carcinoma Hepatocelular/cirurgia , Falência Renal Crônica/cirurgia , Transplante de Rim/métodos , Cirrose Hepática/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/métodos , Carcinoma Hepatocelular/complicações , Hepatite C Crônica/complicações , Humanos , Falência Renal Crônica/complicações , Cirrose Hepática/complicações , Neoplasias Hepáticas/complicações , Masculino , Pessoa de Meia-Idade , Espaço Retroperitoneal/cirurgia , Resultado do Tratamento
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 157: 227-237, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26774814

RESUMO

The present study presents and discusses the conformational preferences of Norspermidine (NSpd). The effects of varying the dielectric constant on the conformational preferences are discussed, with a view to infer which conformation will correspond to the most stable in the pure condensed liquid phase. Within the same context, a set of NSpd-NH3 molecular adducts were simulated in order to determine the relevance of intermolecular hydrogen bonding on the overall stability and relative positioning of the respective vibrational frequencies. The calculations presently performed allowed a reassessment of the vibrational assignments for NSpd. A full assignment of the NSpd vibrational spectra is presented, with special emphasis being given to the vibrational modes that proved to be most affected by hydrogen bonding. The various inconsistencies of a prior study found in the literature were identified and rectified.

3.
J Mol Model ; 21(10): 266, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26386957

RESUMO

The present work provides sets of correction factors to adjust the calculated vibrational frequencies of a series of α,ω-diamines hydrochloride salts to account for the intermolecular interactions with the counterion. The study was performed using different theory levels for predicting the vibrational data of isolated dicationic α,ω-diamines and their hydrochloride forms, with and without the explicit account of the interactions with the chloride counterions. Different sets of correction factors were determined for each theory level considering the four smallest elements for the α,ω-diamines series, while their transferability and reliability was evaluated considering the larger elements of the series. The theory level simplification was also evaluated and was found to neither compromise the vibrational frequencies estimates nor the magnitude and accuracy of the pre-defined scaling factors. This suggests that transferability of the correction factors is possible not only for different diamines but also between different levels of theory with the averaged group correction factor, ζ g (a) , being the best choice to account for the effects of the N-H · · · Cl interactions. The possibility of simplifying the theory level without compromising efficiency and accuracy is additionally of utmost importance. This computational approach can constitute a valuable tool in the future for studying the hydrochloride forms of larger and more complex diamine systems. Graphical Abstract A computational approach that may constitute a valuable tool for studying the hydrochloride forms of large and complex diamine systems. Correction factors to adjust the vibrational frequencies calculated for isolated dicationic primary diamines for the effects of the interactions with chloride counterions, without their explicit account in the calculations, are presented and evaluated for eficiency.

4.
Anal Chem ; 82(4): 1245-52, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20088546

RESUMO

The interaction of double-stranded DNA with two polynuclear Pd(II) chelates with the biogenic polyamines spermidine (Spd) and spermine (Spm), Pd(II)-Spd and Pd(II)-Spm, as well as with the free ligands Spd and Spm, was studied using atomic force microscopy (AFM) at a highly oriented pyrolytic graphite (HOPG) surface, voltammetry at a glassy carbon (GC) electrode, and gel electrophoresis. The AFM and voltammetric results showed that the interaction of Spd and Spm with DNA occurred even for a low concentration of polyamines and caused no oxidative damage to DNA. The Pd(II)-Spd and Pd(II)-Spm complexes were found to induce greater morphological changes in the dsDNA conformation, when compared with their ligands. The interaction was specific, inducing distortion and local denaturation of the B-DNA structure with release of some guanine bases. The DNA strands partially opened give rise to palladium intra- and interstrand cross-links, leading to the formation of DNA adducts and aggregates, particularly in the case of the Pd(II)-Spd complex.


Assuntos
Poliaminas Biogênicas/química , Quelantes/química , DNA/metabolismo , Compostos Organometálicos/química , Compostos Organometálicos/metabolismo , Paládio/química , Animais , Carbono/química , Bovinos , DNA/química , Eletroquímica , Eletrodos , Eletroforese , Vidro/química , Grafite/química , Ligantes , Microscopia de Força Atômica , Modelos Moleculares , Conformação de Ácido Nucleico , Oxirredução , Propriedades de Superfície
5.
Bioelectrochemistry ; 78(2): 97-105, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19766544

RESUMO

Polynuclear Pd(II) complexes with biogenic polyamines present great potential clinical importance, due to their antiproliferative and cytotoxic activity coupled to less severe side-effects. The adsorption process and the redox behaviour of two polynuclear palladium chelates with spermine (Spm) and spermidine (Spd), Pd(II)-Spm and Pd(II)-Spd, as well as of their ligands Spm and Spd, were studied using atomic force microscopy (AFM) and voltammetry at highly oriented pyrolytic graphite and glassy carbon electrodes. AFM revealed different adsorption patterns and degree of surface coverage, correlated with the chelate structure, concentration of the solution, applied potential and voltammetric behaviour of the Spm, Spd, Pd(II)-Spm and Pd(II)-Spd systems. The voltammetric study of Spm and Spd showed that these biogenic polyamines undergo an irreversible and pH-dependent oxidation. In acid medium the polyamines are fully protonated, rendering their oxidation more difficult. With increasing pH the oxidation potential for both Spm and Spd is shifted to less positive values, indicating a greater ease of oxidation in alkaline medium. The Pd(II)-Spm and Pd(II)-Spd complexes dissociate at high negative or high positive potentials. The application of a positive potential induced the oxidation of these Pd complexes and the formation of mixed layers of palladium oxides, Spm/Spd and Pd(II)-Spm/Pd(II)-Spd.


Assuntos
Microscopia de Força Atômica , Compostos Organometálicos/química , Paládio/química , Espermidina/química , Espermina/química , Adsorção , Carbono/química , Quelantes/química , Eletroquímica , Eletrodos , Vidro/química , Concentração de Íons de Hidrogênio , Ligantes , Oxirredução
6.
Bioorg Med Chem ; 12(13): 3581-9, 2004 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15186842

RESUMO

The antiproliferative and cytotoxic properties of polyphenolic acid derivatives, structurally related with the natural models caffeic and gallic acids, have been tested in human cervix adenocarcinoma cells (HeLa). Simultaneous structural information was obtained for these compounds through theoretical ab initio methods. This study was conducted for the following esters: methyl caffeate (MC, 1), propyl caffeate (PC, 2), octyl caffeate (OC, 3), methyl gallate (MG, 4), propyl gallate (PG, 5) and octyl gallate (OG, 6). A significant growth-inhibition effect was assessed for some of these compounds, clearly dependent on their structural characteristics. Marked structure-activity relationships (SARs)--namely the number of hydroxyl ring substituents--were found to rule the biological effect of such systems.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Ácidos Cafeicos/química , Ácidos Cafeicos/farmacologia , Ácido Gálico/química , Ácido Gálico/farmacologia , Hidroxibenzoatos/farmacologia , Antineoplásicos/síntese química , Ácidos Cafeicos/síntese química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Ésteres/química , Ácido Gálico/síntese química , Humanos , Hidroxibenzoatos/síntese química , Hidroxibenzoatos/química , Concentração Inibidora 50 , Metilação , Estrutura Molecular , Relação Estrutura-Atividade
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