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EN
The paper presents problems concerning the evolution of haemoglobin. The main stages of Hb evolution: globin gene evolution, formation and solubility of Hb tetramer and functional Hb regulation by allosteric effectors have been presented. The gene duplication, occuring during the formation of fetal and embryonal Hb as well as the evolution rate of vertebrate Hb were discussed. The authors presented the role of exons, introns and pseudogens in the evoluing of globin and discussed the posibility of the acceleration of evolutionary process by means of exon-intron recombinations.
EN
In this work the effect of Paraquat (PQ) and Graraoxone (GX) on isolated human and carp hemoglobins was studied. Degradation products of PQ were isolated from GX solution by thin layer chromatography on silica gel platelets. Purity of the GX fractions obtained was verified on the basis of silica gel rechromatography. The fractions were identified by IR, UV and visible spectra. Binding of PQ degradation products to hemoglobin was studied by molecular filtration through a Sephadex G-50 column. Interaction of GX fractions with hemoglobin was studied by the spectrophotometric method. Absorption spectra were recorded in the X = 200-900 nm range in 30-min intervals, between 0 and 3 hrs of incubation. Effect of pH of the medium on the amount of hemoglobin-bound ligand was determined, and the reactivity of the GX fractions obtained was compared with those of PQ and GX. Conditions of the strongest and the weakest binding of the ligands were identified. The studies performed point to a considerable importance of Hb in the transport of PQ and its degradation products to various tissues. The stronger binding of these ligands by carp Hb confirms that fishes are more sensitive to poisoning by bipyridyl derivatives as compared with mammals (primates).
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EN
The dioxins can reach the environment, can be also accumulated in living organisms and make changes in normal function of these organisms. The article is a briefly review concerns the toxity effect of dioxins on living organisms particularly on their cell membrane. This review surveys the current state of knowledge concerning the mechanism of action of 2,3,7,8-tetrachlorodibenzo-p-dioxin on the animals.
EN
The phenoxyherbiddes are commonly used in Poland. In great numbers the herbicides can reach the environment and be accumulated in living organisms. The reactions of the degradations of those herbicides may lead to create many of their derivatives. Some of them may demonstrate greater degree of their toxical action in compare with original substrate. Among many of the toxical effects we should pay special attention to the tumor and mutagen changes which have been observed among organisms (mammals including human being) exposed to the influence of these herbicides. Main participation in the detoxication of discussing compounds possess microorganisms which use them as a source of carbon and energy.
EN
Qualitative analysis of the effect of ethylene glycol (EG) on the stability of the native structure of monomeric and dimeric methemoglobins isolated from larvae of Chironomus thummi thummi (CTT Hb) was performed by measurements of thermodynamic parameters of denaturation employing the equilibrium method. Results of denaturation studies at various pH conditions demonstrate that the stability of dimeric CTT Hb is close to that of human Hb while monomeric components show a highter lability. The dependence of denaturation enthalpy on the EG concentration is slightly different for monomeric and dimeric components. For dimeric Hb a considerable decrease of denaturation energy was found already at very low EG concentration which is probably due to the disturbance of interaction between the dimeric - forming chains and, as a consequence, to their dissociation. The futher course of the curves is similar for both Hb deriveratives: an increase in the denaturation energy is observed, peaking at the EG molar fraction of 0.04-0.05, folowed by its rapid decrease. The obtained results are in agreement with the following hypothesis. The structal and dynamic stability of globular proteins is controlled by interactions with the surrounding water molecules. Addition of an organic solvent, possessing both hydrophilic and hydrophobic properties as EG, to the medium, disturbs the native protein conformation by change of the structure of its hydration shell. At appropriate concentrations, EG makes the protein to acquire the supernative structure which is reflected by changes in absorption spectra in the UV range demonstrating alterations in the surrounding of the hydrophobic residues. Highter EG concentrations are sufficient to form a new hydration shell of the protein molecule enducing its different special organization.
PL
Preparaty globiny przechowywano w obecności ATP, stosując stężenie ATP: tetramer Hb = 2 : 1 w 8 M roztworze mocznika de jonizowanego z dodatkiem β--merkaptoetanolu, w temperaturze +4°C. w tych samych warunkach przechowywano próby kontrolne, tj. preparaty globiny bez ATP. Rozdziały α i β globiny wykonano metodą Clegga na kolumnach z CM-32 celulozą, oznaczając zawartość ot i |3 łańcuchow globiny po 24, 48, 72 i 96 godzinach przechowywania. Czystość otrzymanych α i β łańcuchów globiny sprawdzano metodą ogniskowania izoelektrycznego w żelu poliakryloamidowym z 8 M mocznikiem i amfoliną o pH 3,5-10,0. Skład aminokwasowy α i β globiny oznaczano metodą automatycznej analizy aminokwasow. Stwierdzono, że w probach kontrolnych zawartość łańcucha β zmniejszała się z 30 mg do ok. 15 mg w okresie 48-96 godzin przechowywania. W próbach przechowywanych z dodatkiem ATP zawartość łańcucha zmniejszała się do ok. 21 mg. Uzyskane wyniki wskazują na stabilizujący wpływ ATP na łańcuchy β. Zawartość łańcucha α zmieniała się nieznacznie zarówno w próbach kontrolnych jak i przechowywanych w obecności ATP.
PL
Uzyskane wyniki świadczą, że oderwanie wolnych i słabo związanych fosforanów organicznych nie wpływa w istotny sposób na powinowactwo tlenowe Hb wołowej. Zastosowany w pracy dodatek 2,3-DPG, dziesiyciokrotnle przekraczający wartości fizjologiczne, powoduje wówczas spadek powinowactwa tlenowego. Łańcuchy β-globiny wołowej wykazują mniejszą trwałość niż łańcuchy α- -globiny. Dodatek 2,3-DPG nie wywiera wpływu na trwałość łańcucha β-hemoglobiny wołowej, ma więc inne działanie niż ATP, który jak stwierdzono w poprzedniej pracy, ma działanie stabilizujące na ten łańcuch.
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