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1.
Chem Asian J ; 14(17): 2979-2987, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31298502

RESUMO

New nickel-based complexes of 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (dpp-bian) with BF4 - counterion or halide co-ligands were synthesized in THF and MeCN. The nickel(I) complexes were obtained by using two approaches: 1) electrochemical reduction of the corresponding nickel(II) precursors; and 2) a chemical comproportionation reaction. The structural features and redox properties of these complexes were investigated by using single-crystal X-ray diffraction (XRD), cyclic voltammetry (CV), and electron paramagnetic resonance (EPR) and UV/Vis spectroscopy. The influence of temperature and solvent on the structure of the nickel(I) complexes was studied in detail, and an uncommon reversible solvent-induced monomer/dimer transformation was observed. In the case of the fluoride complex, the unpaired electron was found to be localized on the dpp-bian ligand, whereas all of the other nickel complexes contained neutral dpp-bian moieties.

2.
Org Biomol Chem ; 5(6): 976-81, 2007 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-17340014

RESUMO

Two nitroxide methanofullerenes was synthesized for the first time, and their structures and biological activities studied. It was shown by X-ray single crystal analysis that the methanofullerene with two nitroxide groups forms a 1 : 2 inclusion complex with chloroform and has a nearly tetrahedral (diamond-like) arrangement of fullerene-fullerene interactions in the crystal. For the first time, it has been found that malonate nitroxide methanofullerene in combination with the known anticancer drug cyclophosphamide (CPA) shows high antitumor activity against leukemia P-388.


Assuntos
Fulerenos/química , Fulerenos/farmacologia , Animais , Cromatografia Líquida de Alta Pressão , Cristalografia por Raios X , Ciclofosfamida/uso terapêutico , Espectroscopia de Ressonância de Spin Eletrônica , Fulerenos/uso terapêutico , Leucemia/tratamento farmacológico , Masculino , Camundongos , Modelos Moleculares , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Eur J Appl Physiol ; 97(6): 716-22, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16791601

RESUMO

The primary purpose of this study was to examine the effects of high-intensity acute exercise on neutrophil infiltration in different muscle fiber types of untrained rats and to compare postexercise neutrophil accumulation in muscles of untrained and trained animals. The effect of high-intensity acute exercise on blood neutrophil degranulation reaction in trained animals was also elucidated. Neutrophil enzyme myeloperoxidase (MPO) was determined as a measure of neutrophil migration into muscles and blood neutrophil degranulation. Male albino rats were subjected to acute exercise and 5 weeks of training. The used model of intensive acute exercise consisted of 5, 15, and 25 intermittent swimming bouts with the addition of weight (8% of total body mass) for 1-min each, followed by 1.5-min rest intervals. MPO was analyzed in quadriceps muscle (white and red portion) and in soleus muscle 24 h after acute exercise. MPO content in resting blood plasma and neutrophils was determined 48-h following the completion of a training process. In addition, MPO content in the trained rats was measured immediately (in blood plasma and neutrophils) after and 24 h (in muscles) following a single-bout of exercise to exhaustion. The remaining two-third of the trained animals were exposed to a single-bout of nonstop swimming with the addition of 6% body mass until exhaustion. These animals were sacrificed immediately and 24 h after loaded swimming to analyze leukocyte count, MPO content in blood plasma and neutrophils and in muscles, respectively. About 24 h after exercise MPO concentrations in the red portion of quadriceps muscle and in soleus muscle were 4-7-fold higher as compared to the white portion of m. quadriceps. There was an association between the quantity of repetitive bouts of swimming and MPO content in the muscles. The duration of swimming to exhaustion of trained rats was 3.8-fold longer than untrained sedentary control. At rest, plasma MPO concentration was found to be 40% higher in trained rats compared to untrained controls (P < 0.05). Postexercise plasma MPO concentrations were significantly higher both in untrained (+137%; P < 0.05) and trained (+81%; P < 0.05) rats compared to resting values. At rest neutrophil MPO concentration was found to be 33% lower in trained rats compared to untrained controls (P < 0.05). There were no significant differences in muscle MPO concentrations between untrained and trained rats at rest. A single-bout of exercise to exhaustion produced a greater increase in MPO content in untrained compared to trained rats. The data suggest that postexercise neutrophil infiltration is more intensive in red fibers types compared to white fiber types. A smaller neutrophil infiltration in muscles of trained animals after exhaustive exercise suggests a protective effect of previous training to muscle injury.


Assuntos
Músculo Esquelético/citologia , Neutrófilos/enzimologia , Peroxidase/metabolismo , Condicionamento Físico Animal/fisiologia , Animais , Ácido Láctico/sangue , Contagem de Leucócitos , Masculino , Fibras Musculares de Contração Rápida/citologia , Neutrófilos/citologia , Peroxidase/sangue , Ratos , Natação/fisiologia
4.
Eur J Appl Physiol ; 89(3-4): 257-62, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12736833

RESUMO

Exercise sessions (swimming in rats and treadmill running in humans) resulted in stimulation of neutrophil degranulation in the experiments with animals and in the human study. Myeloperoxidase (MPO) (+67%) and lysozyme (+51%) quantities in the plasma of rats increased significantly immediately after exercise. The blood plasma lysozyme concentration was increased by 41% at the 6th min of treadmill exercise in athletes. The blood concentrations of neutrophil proteins normalized both in humans and animals at rest. The neutrophil protein concentrations in blood increased in parallel with the decrease of their level in leukocytes. The neutrophil capacity for an oxidative burst was not changed by the exercise, but decreased for 3-6 h in the post-exercise period. Such dynamics of the oxidative burst activity suggest a lack of association between this parameter and the degranulation process. The neutrophil proteins that appear in blood during degranulation can be involved in enhancing the bactericidal potency of blood, the activation of granulopoiesis, neutrophil efflux from bone marrow, and the conditioning of blood endothelium for leukocyte extravasation.


Assuntos
Exercício Físico/fisiologia , Muramidase/sangue , Ativação de Neutrófilo/fisiologia , Neutrófilos/enzimologia , Peroxidase/sangue , Resistência Física/fisiologia , Corrida/fisiologia , Natação/fisiologia , Adolescente , Adulto , Animais , Humanos , Masculino , Muramidase/metabolismo , Neutrófilos/fisiologia , Peroxidase/metabolismo , Condicionamento Físico Animal/fisiologia , Ratos , Explosão Respiratória/fisiologia , Especificidade da Espécie
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