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1.
Mol Biol Rep ; 47(10): 7451-7457, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32910289

RESUMO

Obesity is a widespread problem within modern society, serving to increase the risk of cardiovascular, metabolic, and neurodegenerative disorders. Peroxisome proliferator-activated receptor gamma (PPARγ) and PPARγ coactivator 1 α (PGC1α) play a key role in the regulation of cellular energy metabolism and is implicated in the pathology of these diseases. This study examined the association between polymorphisms of the PPARG and PPARGC1A genes and individual variability in weight loss in response to physical activity intervention. 39 obese Ukrainian women (44.4 ± 7.5 years, BMI > 30.0 kg/m2) undertook a 3-month fitness program whilst following a hypocaloric diet (~ 1500 cal). Anthropometric and biochemical measurements took place before and after the program. Single nucleotide polymorphisms within or near PPARG (n = 94) and PPARGC1A (n = 138) were identified and expression of PPARG mRNA was measured via reverse transcription and amplification. The association between DNA polymorphisms and exercise-induced weight loss, initial body mass, biochemistry and PPARG expression was determined using one-way analysis of variance (ANOVA). The present intervention induced significant fat loss in all participants (total fat: 40.3 ± 5.3 vs 36.4 ± 5.7%; P < 0.00001). Only one polymorphism (rs17650401 C/T) within the PPARGC1A gene was found to be associated with fat loss efficiency after correction for multiple testing, with T allele carriers showing the greatest reduction in body fat percentage (2.5-fold; P = 0.00013) compared to non-carriers. PPARGC1A (rs17650401) is associated with fat loss efficiency of the fitness program in obese women. Further studies are warranted to test whether this variation is associated with fat oxidation.


Assuntos
Exercício Físico , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Polimorfismo de Nucleotídeo Único , Redução de Peso/genética , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Ucrânia
2.
Bioresour Technol ; 193: 469-76, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26162525

RESUMO

The eicosapentaenoic acid (EPA) containing marine microalga Nannochloropsis oculata was grown in an effluent from anaerobic digestion of excess activated sludge from a wastewater treatment plant serving a combination of a pulp and a paper mill and a municipality (digester effluent, DE), mixed with the effluent of the same wastewater treatment plant. The maximum specific growth rate and photosynthesis of N. oculata were similar in the DE medium and in artificial sea water medium (ASW) but after 7 days, algae grown in the DE medium contained seven times more triacylglycerols (TAGs) per cell than cells grown in ASW, indicating mild stress in the DE medium. However, the volumetric rate of EPA production was similar in the ASW and DE media. The results suggest that N. oculata could be used to produce EPA, utilizing the nutrients available after anaerobic digestion of excess activated sludge of a pulp and paper mill.


Assuntos
Ácido Eicosapentaenoico/biossíntese , Resíduos Industriais/análise , Papel , Estramenópilas/crescimento & desenvolvimento , Águas Residuárias/química , Biodegradação Ambiental , Metais Pesados/análise , Fotobiorreatores/microbiologia , Fotossíntese , Água do Mar , Estramenópilas/metabolismo , Eliminação de Resíduos Líquidos
3.
Photochem Photobiol ; 90(1): 79-84, 2014 01.
Artigo em Inglês | MEDLINE | ID: mdl-23931185

RESUMO

The effect of intermolecular proton transfer on the spectral properties of levofloxacin in the ground and excited electronic states was studied. The preferred direction of possible protolytic reactions induced by UV irradiation in this compound was studied. It was found that the proton transfer processes have a considerable effect on the capability of the compound to emit light and occur on the nanosecond timescale. The photochemical reactions of the tree forms of levofloxacin (pH: 4.0, 7.0, 10.0) were studied by laser flash photolysis and product studies. Irradiation at pH 4 yielded a pulse and transient (λmax  = 395, 515, 575 nm) assigned to the protonated triplet. Irradiation at pH 7 yielded a transient species (λmax  = 525, 610 nm) assigned to the neutral form. Protonation of the anionic singlet excited state was also observed (λmax  = 440, 570, 680 nm).

4.
Biochim Biophys Acta ; 1818(11): 2563-71, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22664062

RESUMO

Classical atom-scale molecular dynamics simulations, constrained free energy calculations, and quantum mechanical (QM) calculations are employed to study the diffusive translocation of ciprofloxacin (CPFX) across lipid membranes. CPFX is considered here as a representative of the fluoroquinolone antibiotics class. Neutral and zwitterionic CPFX coexist at physiological pH, with the latter being predominant. Simulations reveal that only the neutral form permeates the bilayer, and it does so through a novel mechanism that involves dissolution of concerted stacks of zwitterionic ciprofloxacins. Subsequent QM analysis of the observed molecular stacking shows the important role of partial charge neutralization in the stacks, highlighting how the zwitterionic form of the drug is neutralized for translocation. The findings propose a translocation mechanism in which zwitterionic CPFX molecules approach the membrane in stacks, but they diffuse through the membrane as neutral CPFX monomers due to intermolecular transfer of protons favored by partial solvation loss. The mechanism is expected to be of importance in the permeation and translocation of a variety of ampholitic drugs with stacking tendencies.


Assuntos
Antibacterianos/metabolismo , Ciprofloxacina/metabolismo , Bicamadas Lipídicas , Transporte Biológico , Modelos Moleculares , Teoria Quântica
5.
J Fluoresc ; 21(6): 2117-22, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21750893

RESUMO

Electronic absorption, luminescence, IR and Raman spectra of polymorphous forms of fluoroquinolones were investigated. Assignment of the band maxima due to π→π* and n→π* electronic transitions were done. The structural changes are responsible for the absorption band modifications. One-electron transitions in the long wavelength region, excitation wavelengths, oscillator strengths and involved molecular orbitals for the zwitter-ionic and cationic protonated forms for different fluoroquinolones were calculated with quantum-chemical and molecular dynamic methods. The electron density redistributions on the FQs separate fragments during the photoexcitation to the S(1)*-state were carry out by Mulliken calculations. It was shown that the degree of neutral and zwitter-ion FQs penetration through the bacterium membrane is different.


Assuntos
Fluoroquinolonas/química , Prótons , Luminescência , Teoria Quântica , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Análise Espectral Raman
6.
J Fluoresc ; 21(3): 1293-300, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21229296

RESUMO

Electronic absorption and luminescent spectra of nonfluorinated nalidixic (nlqH) and pipemidic acid (pifqH), monofluoroquinolones - norfloxacin (nfqH) and pefloxacin (pfqH) as well as of their difluorinated analogs 1-ethyl-6,8-difluoro-1,4-dihydro-7-(1-(4-methylpiperazinyl) - 4-oxo-3-quinolinecarboxylic (mdfqH) acid and 1-ethyl-6,8-difluoro-1,4-dihydro-7-(1-piperazinyl) - 4-oxo-3-quinolinecarboxylic acid (dfqH) - were investigated. Quantum yields, lifetimes of excited states and rate constants of radiative and nonradiative transitions of the compounds were measured. The Mulliken charges of atoms from these compounds were calculated by quantum-chemical complex GAMESS. Differences in the electronic structures of these compounds and their spectral-luminescent characteristics were compared with the data of the phototoxicity degree of fluoroquinolones. Analysis of the Mulliken charges of the difluoroquinolones points to the changes of the redistribution of the electron density along π-conjugated system, and on the oxygen atoms of the carbonyl and carboxyl groups. The analysis of the molecular orbitals involved in the electronic transitions of the compounds revealed that both defluorination and piperazine photolysis are photodecomposition mechanisms which may take place in the excited states of these compounds. The relationship between the location order of the π-π* excited levels of the FQs and the degree of their phototoxicity has been determined.


Assuntos
Fluoroquinolonas/química , Luminescência , Modelos Moleculares , Elétrons , Fluoroquinolonas/efeitos da radiação , Fotólise
7.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 11): m1377, 2009 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-21578127

RESUMO

In the title compound, (C(4)H(12)N(2))[AuCl(4)](2)·2H(2)O, the Au(III) atom has a square-planar geometry. The piperazinium dication lies on an inversion centre and adopts a typical chair conformation. In the crystal, a combination of N-H⋯O, N-H⋯Cl and O-H⋯Cl hydrogen bonds results in the formation of a three-dimensional network.

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