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1.
Chem Zvesti ; 72(10): 2599-2606, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30147226

RESUMO

The aim of this experiment was to assess the range of proteolysis and biogenic amine content in the selected rennet- and acid-curd cheeses available on the Polish market, randomly chosen for the analyses: three ripened hard with eyes cheeses, three ripened hard smooth cheeses, three ripened soft moulded cheeses, three fresh unripened acid-curd cheeses, three ripened acid-curd cheeses with slimming bacteria-fried, and three ripened acid-curd cheeses with smear bacteria. The results allowed calculating the subsequent indexes and depth of proteolysis. It was found that the acid-curd short ripened cheese (harzer) was characterized by the greatest range of proteolysis and the biogenic amine content in comparison to other rennet- and acid-curd cheeses. In the assessed acid- and rennet-curd cheeses, the dominant amines were as follow, cadaverine, tyramine, and putrescine, with the exception of cheddar in which the histamine was predominant.

2.
J Chem Phys ; 138(12): 124506, 2013 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-23556735

RESUMO

The work presents a theory of nuclear ((1)H) spin-lattice relaxation dispersion for solutions of (15)N and (14)N radicals, including electron spin relaxation effects. The theory is a generalization of the approach presented by Kruk et al. [J. Chem. Phys. 137, 044512 (2012)]. The electron spin relaxation is attributed to the anisotropic part of the electron spin-nitrogen spin hyperfine interaction modulated by rotational dynamics of the paramagnetic molecule, and described by means of Redfield relaxation theory. The (1)H relaxation is caused by electron spin-proton spin dipole-dipole interactions which are modulated by relative translational motion of the solvent and solute molecules. The spectral density characterizing the translational dynamics is described by the force-free-hard-sphere model. The electronic relaxation influences the (1)H relaxation by contributing to the fluctuations of the inter-molecular dipolar interactions. The developed theory is tested against (1)H spin-lattice relaxation dispersion data for glycerol solutions of 4-oxo-TEMPO-d16-(15)N and 4-oxo-TEMPO-d16-(14)N covering the frequency range of 10 kHz-20 MHz. The studies are carried out as a function of temperature starting at 328 K and going down to 290 K. The theory gives a consistent overall interpretation of the experimental data for both (14)N and (15)N systems and explains the features of (1)H relaxation dispersion resulting from the electron spin relaxation.

3.
J Chem Phys ; 138(6): 064304, 2013 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-23425468

RESUMO

The zero-field splitting (ZFS) is an important quantity in the electron spin Hamiltonian for S = 1 or higher. We report calculations of the ZFS in some six- and five-coordinated nickel(II) complexes (S = 1), using different levels of theory within the framework of the ORCA program package [F. Neese, Wiley Interdiscip. Rev.: Comput. Mol. Sci. 2, 73 (2012)]. We compare the high-end ab initio calculations (complete active space self-consistent field and n-electron valence state perturbation theory), making use of both the second-order perturbation theory and the quasi-degenerate perturbation approach, with density functional theory (DFT) methods using different functionals. The pattern of results obtained at the ab initio levels is quite consistent and in reasonable agreement with experimental data. The DFT methods used to calculate the ZFS give very strongly functional-dependent results and do not seem to function well for our systems.

4.
J Chem Phys ; 138(2): 024506, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23320703

RESUMO

For nitroxide radicals in solution one can identify three frequency regimes in which (1)H spin-lattice relaxation rate of solvent molecules depend linearly on square root of the (1)H resonance frequency. Combining a recently developed theory of nuclear (proton) spin-lattice relaxation in solutions of nitroxide radicals [D. Kruk et al., J. Chem. Phys. 137, 044512 (2012)] with properties of the spectral density function associated with translational dynamics, relationships between the corresponding linear changes of the relaxation rate (for (14)N spin probes) and relative translational diffusion coefficient of the solvent and solute molecules have been derived (in analogy to (15)N spin probes [E. Belorizky et al., J. Phys. Chem. A 102, 3674 (1998)]). This method allows a simple and straightforward determination of diffusion coefficients in spin-labeled systems, by means of (1)H nuclear magnetic resonance (NMR) relaxometry. The approach has thoroughly been tested by applying to a large set of experimental data-(1)H spin-lattice relaxation dispersion results for solutions of different viscosity (decalin, glycerol, propylene glycol) of (14)N and (15)N spin probes. The experiments have been performed versus temperature (to cover a broad range of translational diffusion coefficients) using field cycling spectrometer which covers three decades in (1)H resonance frequency, 10 kHz-20 MHz. The limitations of NMR relaxometry caused by the time scale of the translational dynamics as well as electron spin relaxation have been discussed. It has been shown that for spin-labeled systems NMR relaxometry gives access to considerably faster diffusion processes than for diamagnetic systems.

5.
J Chem Phys ; 135(22): 224511, 2011 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-22168707

RESUMO

A general theory of lineshapes in nuclear quadrupole resonance (NQR), based on the stochastic Liouville equation, is presented. The description is valid for arbitrary motional conditions (particularly beyond the valid range of perturbation approaches) and interaction strengths. It can be applied to the computation of NQR spectra for any spin quantum number and for any applied magnetic field. The treatment presented here is an adaptation of the "Swedish slow motion theory," [T. Nilsson and J. Kowalewski, J. Magn. Reson. 146, 345 (2000)] originally formulated for paramagnetic systems, to NQR spectral analysis. The description is formulated for simple (Brownian) diffusion, free diffusion, and jump diffusion models. The two latter models account for molecular cooperativity effects in dense systems (such as liquids of high viscosity or molecular glasses). The sensitivity of NQR slow motion spectra to the mechanism of the motional processes modulating the nuclear quadrupole interaction is discussed.

6.
Horm Metab Res ; 30(3): 158-61, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9566860

RESUMO

Fifteen out of the forty-five patients with long-standing diabetes mellitus type I were characterised by the presence of TNFalpha in the sera when examined on several occasions over a period of five years. TNFalpha-producing patients had a better control of the disease and a smaller percentage of them suffered from diabetic complications as compared with those not producing this cytokine. TNFalpha-producing patients had lower levels of the proinflammatory markers - IL6 and CRP, and higher concentrations of ACTH and cortisol than those not producing this cytokine. We suggest that TNFalpha released systemically in diabetic patients stimulates the hypophysis-adrenal axis, and in that way indirectly ameliorates autoimmune response occurring during the advanced phase of the disease.


Assuntos
Diabetes Mellitus Tipo 1/sangue , Fator de Necrose Tumoral alfa/metabolismo , Hormônio Adrenocorticotrópico/sangue , Adulto , Proteína C-Reativa/metabolismo , Diabetes Mellitus Tipo 1/complicações , Hemoglobinas Glicadas/metabolismo , Humanos , Hidrocortisona/sangue , Interleucina-2/sangue , Interleucina-6/sangue , Pessoa de Meia-Idade , Células Tumorais Cultivadas
7.
Pol Merkur Lekarski ; 1(2): 118-9, 1996 Aug.
Artigo em Polonês | MEDLINE | ID: mdl-9156909

RESUMO

The authors described developmental anomaly of the right kidney associated with hypertension and pyonephrosis in a 37 years old male. The authors reported the diagnostic problems in this kind of hypertension. After nephrectomy had been performed the elevated blood pressure returned to normal values without any additional pharmacological treatment.


Assuntos
Hipertensão Renal/etiologia , Rim/anormalidades , Pielonefrite/etiologia , Adulto , Humanos , Rim/cirurgia , Masculino , Nefrectomia
15.
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