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1.
Molecules ; 25(8)2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32316698

RESUMO

Three new 6-methyl-2-oxo-1,2-dihydroquinoline-3-carbaldehyde-thiosemicarbazones-N-4-substituted pro-ligands and their Cu(II) complexes (1, -NH2; 2, -NHMe; 3, -NHEt) have been prepared and characterized. In both the X-ray structures of 1 and 3, two crystallographically independent complex molecules were found that differ either in the nature of weakly metal-binding species (water in 1a and nitrate in 1b) or in the co-ligand (water in 3a and methanol in 3b). Electron Paramagnetic Resonance (EPR) measurements carried out on complexes 1 and 3 confirmed the presence of such different species in the solution. The electrochemical behavior of the pro-ligands and of the complexes was investigated, as well as their biological activity. Complexes 2 and 3 exhibited a high cytotoxicity against human tumor cells and 3D spheroids derived from solid tumors, related to the high cellular uptake. Complexes 2 and 3 also showed a high selectivity towards cancerous cell lines with respect to non-cancerous cell lines and were able to circumvent cisplatin resistance. Via the Transmission Electron Microscopy (TEM) imaging technique, preliminary insights into the biological activity of copper complexes were obtained.

2.
Dalton Trans ; 48(35): 13491-13492, 2019 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-31453993

RESUMO

Correction for 'New light on an old debate: does the RCN-PtCl2 bond include any back-donation? RCN ← PtCl2 backbonding vs. the IR νC[triple bond, length as m-dash]N blue-shift dichotomy in organonitriles-platinum(ii) complexes. A thorough density functional theory - energy decomposition analysis study' by Girolamo Casella et al., Dalton Trans., 2019, DOI: 10.1039/c9dt02440a.

3.
Dalton Trans ; 48(34): 12974-12985, 2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31397469

RESUMO

For a series of organonitrile [RCN (R = Me, CF3, Ph, CH3Ph, CF3Ph)] ligands, the nature of the N-Pt bond in the related cis-/trans-(RCN)2PtCl2 complexes has been computationally investigated by Density Functional Theory. A fragment based bond analysis has been performed in the canonical Kohn-Sham molecular orbitals framework, and it has been ultimately assessed that this bond is characterized both by N→Pt σ and by N←Pt π contributions. Voronoi Deformation Density charges further confirms the occurrence of N←Pt π interactions. Moreover, the Energy Decomposition Analysis-Natural Orbital for Chemical Valence (EDA-NOCV) method shows that the strength of the N←Pt π interaction is not negligible by contributing to about 30-40% of the total orbital interaction. Finally, the well-known νC[triple bond, length as m-dash]N blue-shift occurring upon coordination to PtII, has been thoroughly investigated by exploiting the EDA-NOCV and by evaluating νC[triple bond, length as m-dash]N and force constants. The origin of the νC[triple bond, length as m-dash]N blue-shift in these systems has been discussed on the basis of the CN bond polarization. N←Pt π backbonding causes only a systematic decrease of the observed νC[triple bond, length as m-dash]N blue-shift when compared to the one calculated for RCN-X (X = H+, alkaline, Lewis acids) herein reported (X = purely σ acceptors).

4.
J Inorg Biochem ; 182: 18-28, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29407866

RESUMO

Three new 2-oxo-1,2-dihydrobenzo[h]quinoline-3-carbaldehyde terminal substituted aroylhydrazone ligands (2-Oxo-1,2-dihydrobenzo[h]quinoline-3-carbaldehyde(2'-hydroxybenzoyl)hydrazine, H2L1, 1, 2-Oxo-1,2-dihydrobenzo[h]quinoline-3-carbaldehyde(2'-hydroxybenzoyl)hydrazine, H2L2, 2, 2-Oxo-1,2-dihydrobenzo[h]quinoline-3-carbaldehyde(2'-hydroxybenzoyl)hydrazine, H2L3, 3) and the corresponding novel copper(II) complexes [Cu(L)(CH3OH)(NO3)](L = HL1 (4), HL2 (5), HL3 (6-6+), have been synthesized to compare their coordination behaviour and biological activity with respect to the presence of an OH group in different positions of the phenyl ring in the hydrazone moieties. The new ligands and their copper complexes were characterized by elemental analysis and spectroscopic techniques. The molecular structures of the new complexes 4 and 6-6+ were determined by single crystal X-ray diffraction. The interactions of the free ligands and their copper complexes with calf thymus DNA were tested by absorption measurements and ethidium bromide competitive studies which revealed that all compounds may interact with calf thymus DNA through intercalation. Furthermore, a comparative analysis of the cytotoxic effect of the compounds on a panel of human cancer cell lines showed that the copper complexes exhibited in vitro antitumor activity significantly higher than that of the free ligands and also of cisplatin.


Assuntos
Complexos de Coordenação/síntese química , Complexos de Coordenação/toxicidade , Cobre/química , Compostos Organometálicos/síntese química , Compostos Organometálicos/toxicidade , Quinolinas/química , Linhagem Celular Tumoral , Complexos de Coordenação/química , DNA/efeitos dos fármacos , DNA/genética , Clivagem do DNA/efeitos dos fármacos , Células HCT116 , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Compostos Organometálicos/química , Plasmídeos
5.
Nanomaterials (Basel) ; 7(11)2017 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-29113079

RESUMO

Ferrofluids are nanomaterials consisting of magnetic nanoparticles that are dispersed in a carrier fluid. Their physical properties, and hence their field of application are determined by intertwined compositional, structural, and magnetic characteristics, including interparticle magnetic interactions. Magnetic nanoparticles were prepared by thermal decomposition of iron(III) chloride hexahydrate (FeCl3·6H2O) in 2-pyrrolidone, and were then dispersed in two different fluids, water and polyethylene glycol 400 (PEG). A number of experimental techniques (especially, transmission electron microscopy, Mössbauer spectroscopy and superconducting quantum interference device (SQUID) magnetometry) were employed to study both the as-prepared nanoparticles and the ferrofluids. We show that, with the adopted synthesis parameters of temperature and FeCl3 relative concentration, nanoparticles are obtained that mainly consist of maghemite and present a high degree of structural disorder and strong spin canting, resulting in a low saturation magnetization (~45 emu/g). A remarkable feature is that the nanoparticles, ultimately due to the presence of 2-pyrrolidone at their surface, are arranged in nanoflower-shape structures, which are substantially stable in water and tend to disaggregate in PEG. The different arrangement of the nanoparticles in the two fluids implies a different strength of dipolar magnetic interactions, as revealed by the analysis of their magnetothermal behavior. The comparison between the magnetic heating capacities of the two ferrofluids demonstrates the possibility of tailoring the performances of the produced nanoparticles by exploiting the interplay with the carrier fluid.

6.
J Inorg Biochem ; 155: 1-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26606287

RESUMO

A novel binuclear palladium(II) complex [(AsPh3)2ClPd(L)PdCl] (LPd2) has been synthesized by reacting 2-oxo-1,2-dihydroquinoline-3-carbaldehyde-4(N,N)-dimethylthiosemicarbazone (HL) with [PdCl2(AsPh3)2], and the molecular structure was confirmed by single crystal X-ray diffraction studies. The DNA interactions of the free ligand and of the complex have been evaluated by absorption and ethidium bromide (EB) competitive studies which revealed that the complex could interact with calf thymus DNA (CT-DNA) through intercalation. In addition, the interactions with bovine serum albumin (BSA) were also studied showing that the new binuclear palladium complex had a strong binding affinity with BSA.


Assuntos
DNA/química , Paládio/química , Proteínas/química , Tiossemicarbazonas/química , Cristalografia por Raios X , Ligação Proteica
7.
Cutan Ocul Toxicol ; 35(4): 332-6, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26612003

RESUMO

Hair highlights are quite common procedures carried out in hair salons by using a mixture of a lightening powder containing persulfates with a suspension containing hydrogen peroxide: a representative case of chemical scalp burns is described as a consequence of this treatment. The aim of the paper is to demonstrate the strict relationship between the scalp damage and the commercial products used in a case of hair highlighting. The results of some chemical analyses have been reported, showing, in particular, that the chemical reactivity of the mixture changes in the time, thus strongly suggesting that the procedure for the application of the mixture is critical for the occurrence of possible accidents. The presence in the powder of chemical compounds bearing aliphatic chains as surfactants explains the appearance of dramatic symptoms after days due to a slow dissolution of the oxidant compounds in the stratum corneum of skin with no effect in reducing injury of palliative treatments. Safety suggestions and recommendations for producers and workers are also included.


Assuntos
Queimaduras Químicas/etiologia , Tinturas para Cabelo/toxicidade , Couro Cabeludo/efeitos dos fármacos , Adulto , Queimaduras Químicas/cirurgia , Feminino , Humanos , Peróxido de Hidrogênio/toxicidade , Oxidantes/toxicidade , Couro Cabeludo/lesões , Couro Cabeludo/cirurgia , Sulfatos/toxicidade
8.
Chemistry ; 21(1): 440-7, 2015 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-25353654

RESUMO

Herein a combined NOE NMR/DFT methodology to discriminate between adducts held together by halogen bonding (XB) and other noncovalent interactions (non-XB, such as lone pair/π), based on the determination of the XB donors' and acceptors' relative orientation, is proposed. In particular, (19) F,(1) H HOESY NMR spectroscopy experiments and DFT calculations on different XB donors, such as perfluorohexyl iodide (I1), iodopentafluorobenzene (I2) and bromopentafluorobenzene (Br), combined with different Lewis bases, such as 1,4-diazabicyclo[2.2.2]octane (DABCO) and 2,4,6-trimethylpyridine (Me3 Py), were performed. The results clearly show that in the case DABCO/I1 the XB adduct is practically the only one present in solution, whereas for the other pairs a certain amount of non-XB adduct is present. Combining DFT and HOESY results, the amount of non-XB adducts can be roughly quantified under our experimental conditions as 4 % for DABCO/I2, between 10 and 20 % for Me3 Py/I1 and Me3 Py/I2, and 44 % for DABCO/Br.

9.
Inorg Chem ; 52(10): 5729-41, 2013 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-23647564

RESUMO

The reactions of the nitrile complexes cis- and trans-[PtCl2(NCR)2] (R = Me, Et, CH2Ph, Ph) with an excess of ethanethiol, EtSH, in the presence of a catalytic amount of n-BuLi in tetrahydrofuran (THF), afforded in good yield the bis-imino thioether derivatives cis-[PtCl2{E-N(H)═C(SEt)R}2] (R = Me (1), Et (2), CH2Ph (3), Ph (4)) and trans-[PtCl2{E-N(H)═C(SEt)R}2] (R = Me (5), Et (6), CH2Ph (7), Ph (8)). The imino thioether ligands assumed the E configuration corresponding to a cis addition of the thiol to the nitrile triple bond. The spectroscopic properties of these complexes have been reported along with the molecular structures of 1, 2, and 7 as established by X-ray crystallography which indicated that these compounds exhibit square-planar coordination geometry around the platinum center. Four N-H···Cl intermolecular contacts (N-H···Cl ca. 2.5-2.7 Å) between each chlorine atom and the N-H proton of the imino thioether ligand gave rise to "dimers" Pt2Cl4L4 (L = imino thioether) formed by two PtCl2L2 units. The cytotoxic properties of these new platinum(II) complexes were evaluated against various human cancer cell lines. Among all derivatives, trans-[PtCl2{E-N(H)═C(SEt)CH2Ph}2] showed the greatest in vitro cytotoxic activity being able to decrease cancer cell viability roughly 3-fold more effectively than cisplatin.


Assuntos
Antineoplásicos/farmacologia , Iminas/química , Compostos Organoplatínicos/farmacologia , Sulfetos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células MCF-7 , Modelos Moleculares , Estrutura Molecular , Compostos Organoplatínicos/síntese química , Compostos Organoplatínicos/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
10.
ChemMedChem ; 6(7): 1172-83, 2011 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-21630470

RESUMO

Platinum amidine complexes represent a new class of potential antitumor drugs that contain the imino moiety HN=C(sp(2)) bonded to the platinum center. They can be related to the iminoether derivatives, which were recently shown to be the first Pt(II) compounds with a trans configuration endowed with anticancer activity. The chemical and biological properties of platinum amidine complexes, and more generally of platinum imino derivatives, can be rationally modified through suitable synthetic procedures with the aim of improving their cytotoxicity and antitumor activity. The addition of protic nucleophiles to nitriles coordinated to platinum in various oxidation states can offer a wide variety of complexes with chemical, structural, and physical properties specifically tuned for a more efficacious biological response.


Assuntos
Amidinas/química , Antineoplásicos/química , Complexos de Coordenação/química , Platina/química , Aminas/química , Amônia/química , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Complexos de Coordenação/síntese química , Complexos de Coordenação/farmacologia , Nitrilos/química
11.
J Med Chem ; 53(16): 6210-27, 2010 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-20681543

RESUMO

The reactions of cyclopropylamine, cyclopentylamine, and cyclohexylamine with trans-[PtCl2(NCMe)2] afforded the bis-cationic complexes trans-[Pt(amine)2(Z-amidine)2]2+[Cl-]2, 1-3. The solution behavior and biological activity have been studied in different solvents (DMSO, water, polyethylene glycol (PEG 400), and polyethylene glycol dimethyl ether (PEG-DME 500)). The biological activity was strongly influenced by the cycloaliphatic amine ring size, with trans-[Pt(NH2CH(CH2)4CH2)2{N(H) horizontal lineC(CH3)N(H)CH(CH2)4CH2}2]2+[Cl-]2 (3) being the most active compound. Complex 3 overcame both cisplatin and MDR resistance, inducing cancer cell death through p53-mediated apoptosis. Alkaline single-cell gel electrophoresis experiments indicated direct DNA damage, reasonably attributable to DNA adducts of trans-[PtCl(amine)(Z-amidine)2][Cl] species, which can evolve to produce disruptive and nonrepairable lesions on DNA, thus leading to the drug-induced programmed cancer cell death. Preliminary in vivo antitumor studies on C57BL mice bearing Lewis lung carcinoma highlighted that complex 3 promoted a significant and dose-dependent tumor growth inhibition without adverse side effects.


Assuntos
Amidinas/síntese química , Aminas/síntese química , Antineoplásicos/síntese química , Complexos de Coordenação/síntese química , Platina , Amidinas/química , Amidinas/farmacologia , Aminas/química , Aminas/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisplatino/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Cristalografia por Raios X , Dano ao DNA/efeitos dos fármacos , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Solubilidade , Estereoisomerismo , Relação Estrutura-Atividade , Proteína Supressora de Tumor p53/biossíntese
12.
J Inorg Biochem ; 103(8): 1113-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19560209

RESUMO

A series of new platinum(II) amidine derivatives of the type cis-[PtCl(2){Z-NHC(NHR)Me}(2)] (R=cyclopropyl, 1; cyclopentyl, 2; cyclohexyl, 3) were prepared in high yield by addition of the corresponding cyclic aliphatic amine RNH(2) to the coordinated acetonitrile ligands in cis-[PtCl(2)(NCMe)(2)]. The solution behaviour of 1-3 has been studied in DMSO, PEG 400 (polyethylene glycol) and PEG-DME 500 (polyethylene glycol dimethylether). The amidine complexes 1-3 were evaluated for their cytotoxic properties against a panel of human tumor cell lines containing examples of cervix (HeLa), breast (MCF7), lung (A549) and colon (HCT-15) cancer. Moreover, the amidine complexes were tested for their cytotoxicity against normal human fibroblasts (HFF-1). For comparison purposes, the cytotoxicity of cisplatin was examined under the same experimental conditions. The results obtained showed that PEG and PEG-DME behave as good solvents to carry out biological assays with platinum complexes which are water-insoluble and unstable in DMSO. Complexes 2 and 3 exhibited a biological activity comparable to that of cisplatin.


Assuntos
Amidinas/química , Antineoplásicos/toxicidade , Cisplatino/síntese química , Cisplatino/toxicidade , Compostos Heterocíclicos/química , Solventes/química , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Cisplatino/química , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Soluções
13.
J Inorg Biochem ; 102(4): 882-91, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18267343

RESUMO

New substituted benzyl iminoether derivatives of the type cis- and trans-[PtCl(2){E-N(H)C(OMe)CH(2)-C(6)H(4)-p-R}(2)] (R=Me (1a, 2a), OMe (3a, 4a), F (5a, 6a)) have been synthesized and characterized by elemental analyses, FT-IR spectroscopy and NMR techniques. The iminoether ligands are in the E configuration, which is stable in solution and in the solid state, as confirmed by the (1)H NMR data. Complex trans-[PtCl(2){E-N(H)C(OMe)CH(2)-C(6)H(4)-p-F}(2)] (6a) was also characterized by an X-ray diffraction study. Complexes 1a-6a have been tested against a panel of human tumor cell lines in order to evaluate their cytotoxic activity. cis-Isomers were significant more potent than the corresponding trans-isomers against all tumor cell lines tested; moreover, complexes 1a and 5a showed IC(50) values from about 2-fold to 6-fold lower than those exhibited by cisplatin, used as reference platinum anticancer drug.


Assuntos
Éteres/química , Compostos Organoplatínicos/síntese química , Compostos Organoplatínicos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Compostos Organoplatínicos/química , Espectrofotometria Infravermelho , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
14.
J Med Chem ; 50(19): 4775-84, 2007 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-17713897

RESUMO

New benzyliminoether derivatives [PtCl2{N(H)=C(OMe)CH2Ph}2] of cis (1a, 1b) and trans (2a, 2b) geometry were prepared and characterized by means of elemental analysis, multinuclear NMR and FT-IR techniques, and X-ray crystallography; this latter was carried out for 1b. The cytotoxic properties of these new platinum(II) complexes were evaluated in terms of cell growth inhibition against a panel of different types of human cancer cell lines. cis-[PtCl2{E-N(H)=C(OMe)CH2Ph}2] (1a) was significantly more potent than cisplatin against all tumor cell lines tested, showing IC50 values from about 2- to 17-fold lower than the reference compound. Chemosensitivity tests performed on cisplatin-sensitive and -resistant cell lines have demonstrated that complex 1a is able to overcome cisplatin resistance. Analyzing the mechanism by which complex 1a led to cell death, we have found that it induced apoptosis in a dose-dependent manner, accompanied by the activation of caspase-3. The in vivo studies carried out using two transplantable tumor models (L1210 leukemia and Lewis lung carcinoma) showed that derivative 1a induced a remarkable antitumor activity in both tumor models, as measured by prolonged survival and reduced tumor mass compared to control groups.


Assuntos
Antineoplásicos/síntese química , Éteres/síntese química , Iminas/síntese química , Compostos Organoplatínicos/síntese química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose , Linhagem Celular Tumoral , Cisplatino/farmacologia , Cristalografia por Raios X , DNA/antagonistas & inibidores , DNA/biossíntese , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Éteres/química , Éteres/farmacologia , Feminino , Humanos , Iminas/química , Iminas/farmacologia , Ligantes , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , Compostos Organoplatínicos/química , Compostos Organoplatínicos/farmacologia , Biossíntese de Proteínas/efeitos dos fármacos , RNA/antagonistas & inibidores , RNA/biossíntese , Estereoisomerismo , Relação Estrutura-Atividade
15.
Chemistry ; 10(5): 1281-90, 2004 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-15007818

RESUMO

The Al(III)-binding abilities of two aldaric acids, D-saccharic acid and mucic acid (the neutral form is denoted as H(2)L), were studied in solution by means of pH potentiometric, (1)H and (13)C NMR, and ESI-MS techniques. The most probable conformations and isomeric binding modes of the complexes formed in solution were determined by density functional theory (DFT) calculations. A solid D-saccharic acid complex K(2)[[Al(LH(-2))(H(2)O)](2)].H(2)O was isolated and crystallographically characterised. The two alcoholic hydroxy groups alpha to the terminal COO(-) groups were found to take part in the coordination, but in different ways. One of them coordinates in a bridging mode. Detailed ESI-MS and NMR studies proved that the complex retains its structure in solution. However, depending on the ligand and the pH, such complexes may exist in two isomeric forms. DFT calculations on the ion [[Al(LH(-2))(H(2)O)](2)](2-) revealed that several orbitals participate in stabilizing the dimeric arrangement.


Assuntos
Alumínio/química , Ácido Ascórbico/química , Compostos Organometálicos/química , Soluções/química , Açúcares Ácidos/química , Cristalografia por Raios X , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética/métodos , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray/métodos
16.
Ann Clin Lab Sci ; 34(4): 416-22, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15648783

RESUMO

The aims of this study were to investigate body fluid changes in elderly patients suffering from congestive heart failure (CHF) and to identify the fluid measurement that best characterizes fluid overload states in CHF patients by comparison with normal hydration in the elderly. In a case-controlled experimental design, 72 elderly subjects (65-98 yr), 38 healthy and 34 with CHF, were studied. Total body water (TBW) and extracellular water (ECW) were determined by dilution methods; fat-free mass (FFM) and fat mass (FM) were determined by dual-energy X-ray absorptiometry (DEXA). In healthy subjects, the FFM hydration expressed as TBW% FFM (males 72.0 +/- 4.3 vs females 72.4 +/- 5.0%) and ECW% TBW (males 47.3 +/- 3.4 vs females 47.8 +/- 5.1) were similar in both genders. ECW in liters for FFM and for TBW (ECW% TBW), corrected for body weight, was greater in the group with CHF than in the control group, in both sexes. Among the relative fluid measures, only ECW% TBW [odds ratio (OR) 1.5] independently predicted fluid retention. Having an ECW% TBW greater than 50% corresponded to an OR of about 10. In conclusion, elderly patients suffering from CHF have a characteristic increase in body fluid levels, mainly affecting the extracellular compartment, and ECW% TBW is a useful indicator of fluid retention.


Assuntos
Compartimentos de Líquidos Corporais , Água Corporal , Líquido Extracelular , Insuficiência Cardíaca/metabolismo , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Líquido Extracelular/metabolismo , Feminino , Insuficiência Cardíaca/patologia , Humanos , Masculino
17.
Eur J Med Chem ; 38(7-8): 739-49, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12932905

RESUMO

Oxalate 1,2-diaminocyclohexane platinum (oxaliplatin(R)), a successfully employed platinum compound belonging to the family of Pt-DACH complexes, has been conjugated to different molecular weight poly(ethylene glycols) (PEG) by means of peptide spacers and a malonic acid bidentate residue. Tri- and tetrapeptidic substrates of lysosomal enzymes were used in order to increase the release of Pt-DACH complex inside the cell following endocytosis and enzymatic degradation of the peptide spacer. Other aminoacids (e.g. norleucine) have been also employed. 1H-NMR of some conjugates was performed as characterisation of the product, while 195Pt-NMR analysis was carried out to detect the rearrangement of the platinum complex from the Pt(O,O) to the Pt(O,N) form. The compound PEG(5000)-Nle-malonato-Pt-DACH (4) has been tested against L1210-implanted mice and showed and appreciable increase in cytotoxicity as compared to the reference standard Cl(2)PtDACH.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Cicloexilaminas/síntese química , Cicloexilaminas/farmacologia , Compostos Organoplatínicos/síntese química , Compostos Organoplatínicos/farmacologia , Animais , Ensaios de Seleção de Medicamentos Antitumorais , Estabilidade de Medicamentos , Leucemia L1210/tratamento farmacológico , Leucemia L1210/metabolismo , Espectroscopia de Ressonância Magnética , Malonatos/química , Camundongos , Peso Molecular , Transplante de Neoplasias , Polietilenoglicóis/química , Relação Estrutura-Atividade
18.
Ann Nutr Metab ; 47(3-4): 152-7, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12743467

RESUMO

BACKGROUND/AIMS: Surgical gastric banding procedures induce considerable and rapid weight losses in obese subjects. Nevertheless changes in lean mass and body fluids following these surgical treatments are not well known. METHODS: We studied 6 obese women aged 38-42 years, before, and 8 and 24 weeks after laparoscopic adjustable silicone gastric banding (LAP-BAND(TM)). Fat-free mass (FFM) and fat mass (FM) were investigated using dual energy X-ray absorptiometry (DEXA), while total body water (TBW) and extracellular water (ECW) were assessed by dilution methods. RESULTS: The subjects showed a total weight loss of 16% of initial weight; the weight reduction was greater during the first 8 weeks. FFM decrease after 24 weeks was very limited and represented only 14% of the weight loss. The mean FFM changes per week were similar in the two periods of observation (0-8 and 8-24 weeks after LAP-BAND). TBW showed a global reduction of 2.2 +/- 1.8 litres mainly due to a decline in intracellular water (ICW), while ECW remained constant during weight loss. As a consequence, the ECW/ICW ratio increased after LAP-BAND. CONCLUSION: LAP-BAND seems to achieve satisfactory weight losses while sparing FFM and causing only mild body fluid alterations.


Assuntos
Composição Corporal/fisiologia , Compartimentos de Líquidos Corporais/fisiologia , Gastroplastia , Obesidade Mórbida/metabolismo , Obesidade Mórbida/cirurgia , Perda de Peso/fisiologia , Absorciometria de Fóton , Adulto , Feminino , Humanos , Fatores de Tempo
20.
Inorg Chem ; 35(24): 7089-7094, 1996 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-11666891

RESUMO

In order to obtain information about aluminum(III)-phosphate interactions, potentiometric measurements were carried out to characterize the complex forming properties of Al(III) with organic phosphates, phosphonates, and nucleoside-5'-monophosphates. The aluminum(III)-orthophosphate system is difficult to study due to AlPO(4) precipitation. To overcome this problem, the stability constant logarithms of the 1:1 Al(III) complexes of ligands with the same donor groups (log K(1:1)) were plotted against the basicities of the ligands (log K(PO)3(H)). The resulting linear free energy relation (LFER) indicates that organic phosphates, phosphonates, and uridine-, thymidine-, and guanosine 5'-monophosphates similarly bind Al(III). Adenosine and cytidine 5'-monophosphate fall above the LFER owing to the presence of a second microform with the nucleic base protonated and a hydroxide bound to the Al(III). From the LFER the log stability constant for Al(III) binding to HPO(4)(2-) is estimated as 6.13 +/- 0.05. From the weakness of any soluble orthophosphate complexes of Al(III) we confirm the importance of citrate as the main small molecule Al(3+) binder in the blood serum. The study includes investigation of Al(III) binding to di- and triphosphates, which bind metal ion differently than monophosphates. Structures of the complexes were supported by (31)P NMR measurements.

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