Assuntos
Aclimatação , Membrana Eritrocítica/química , Hemólise , Oncorhynchus mykiss/fisiologia , Animais , Elasticidade , Feminino , Lipídeos/análise , Masculino , Osmose , Proteínas/análise , Estações do Ano , TemperaturaRESUMO
Physicochemical effects of hydrated C(60) fullerenes (HyFn) on serum albumin molecules were studied using ESR spin labeling and differential scanning microcalorimetry. Molecular-colloidal solution of hydrated C(60) fullerenes and their small spherical fractal clusters in water (C(60)FWS), was shown to stabilize protein hydration, and decrease specific surface energy in water-protein matrix in salt solutions. The mechanism of HyFn interaction with protein is discussed in terms of HyFn induced formation of protein clusters and phase transition of hydration water.
Assuntos
Fulerenos/química , Albumina Sérica/química , Calorimetria/métodos , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Conformação Proteica , Soluções , ÁguaRESUMO
Heat-induced hemolysis of erythrocytes was evaluated by the equilibrium method at 54-60 degrees C in patients with lung cancer and donors. Thermal sensitivity of patients differed from that of normal subjects and the seeming energy of erythrocyte lysis activation was lower in patients (230 kJ/mol) than in the controls (345 kJ/mol). Presumably changed structural characteristics of membrane bilayer affected the physicochemical properties of erythrocytes, determining, among other things, thermal resistance of red blood cells.
Assuntos
Eritrócitos , Neoplasias Pulmonares/sangue , Idoso , Interpretação Estatística de Dados , Hemólise , Temperatura Alta , Humanos , Masculino , Pessoa de Meia-Idade , Modelos TeóricosAssuntos
Hemólise , Temperatura Alta , Metemoglobina/química , Oxigênio/sangue , Oxiemoglobinas/química , Animais , Varredura Diferencial de Calorimetria , Bovinos , Peixes , Raposas , Humanos , Desnaturação Proteica , OvinosRESUMO
Effective thermodynamic parameters of activation of label transition between two microsurroundings in water-protein matrix (WPM) of spin-labelled molecules of serum albumin (HSA-SL) in 0.001 M phosphate buffer, pH 7.3 within concentration range of NaCl (m3) (10(-3) M to 2 M and concentration range of protein (m2) 50 to 200 mg/ml were determined. The phase transition (PT) between two structures of water in WPM is revealed within the m3 range 0.01 M to 0.1 M. It is close to the type I PT and more expressed at high protein concentrations. As m3 increases (to 0.2 M when m2 = 50 mg/ml and to 0.7 when m2 = 200 mg/ml) PT-I is transformed into PT of the critical type. This is indicated to zero values of the higher order derivatives of Gibbs energy of activation with respect to salt concentration, as well as by the maximum values of positive disjoining pressure in these points. The biological significance of this phenomenon is discussed.
