Showing papers by "Jagiellonian University published in 1986"
TL;DR: A survey of five diagnostic enzyme loci across the hybrid zone near Cracow in Southern Poland to estimate the dispersal rate, selection pressures, and numbers of loci which maintain this zone suggests that the zone is maintained largely by selection against hybrids.
Abstract: The fire-bellied toads Bombina bombina and B. variegata differ extensively in biochemistry, morphology, and behavior. We use a survey of five diagnostic enzyme loci across the hybrid zone near Cracow in Southern Poland to estimate the dispersal rate, selection pressures, and numbers of loci which maintain this zone. The enzyme clines coincide closely with each other and with morphological and mitochondrial DNA clines. Although the zone lies on a broad transition between environments suitable for bombina and variegata, the close concordance of diverse characters, together with increased aberrations and mortality in hybrids, suggest that the zone is maintained largely by selection against hybrids. There are strong "linkage disequilibria" between each pair of (unlinked) enzyme loci (R = 0.129 [2-unit support limits: 0.119-0.139]). These are probably caused by gene flow into the zone, and they give an estimate of dispersal (σ = 890 [790-940] m gen-½ ). The clines are sharply stepped, with most of the change occurring within 6.15 (5.45-6.45) km, but with long tails of introgression on either side. This implies that the effective selection pressure on each enzyme marker (due largely to disequilibrium with other loci) is s* = 0.17 (0.159-0.181) at the center but that the selection acting directly on the enzyme loci is weak or zero (se < 0.0038). The stepped pattern implies a barrier to gene flow of 220 (48-415) km. This would substantially delay neutral introgression but would have little effect on advantageous alleles; the two taxa need not evolve independently. Strong selection is needed to maintain such a barrier: hybrid populations must have their mean fitness reduced by a factor of 0.65 (0.60-0.77). This selection must be spread over a large number of loci to account for the concordant patterns and the observed cline widths (N = 300 [80-2,000]).
520 citations
TL;DR: Detailed analysis of transient changes in melanin absorbance was demonstrated to be a convenient method for studying redox processes of this substance, as shown by model experiments using ferricyanide and dithionite as oxidising and reducing agents, respectively.
165 citations
TL;DR: It is concluded that cholesterol incorporation increases water accessibility in the hydrophilic loci of the membrane by rigorously determining rigid-limit magnetic parameters of cholestane spin labels in membranes from Q-band second-derivative ESR spectra to monitor the dielectric environment around the nitroxide radical.
150 citations
TL;DR: It was found that the xanthine-xanthine oxidase system is not suitable for studying the reaction of superoxide with melanin, as the enzymatic activity of xanthin oxidase is considerably inhibited by melanin.
114 citations
TL;DR: Electron spin resonance (ESR) spectra from the capsule are sensitive to the concentration of dissolved oxygen and calibration curves are given, and the oxygen concentration was found to rise from a value close to zero when the animal breathes air to a level of 220 μM when theAnimal breaths pure oxygen.
Abstract: Small mice (∼20 g) were anesthetized and placed in a loop-gap resonator of diameter 25 mm resonating at 1.1 GHz. An oxygen-permeable capsule containing 2.5 × 10−2M perdeutero 15N TEMPONE (1-oxyl-2, 2, 6, 6-tetramethyl-4-piperidone) in light paraffin oil was implanted in the peritoneal cavity. Electron spin resonance (ESR) spectra from the capsule are sensitive to the concentration of dissolved oxygen and calibration curves are given. The oxygen concentration was found to rise from a value close to zero when the animal breathes air to a level of 220 μM when the animal breaths pure oxygen. It is speculated that this surprisingly high level is related to the effect of the anesthetic on the cardiovascular system. Encapsulation provides a barrier to spin-label reductants and to paramagnetic metal ions that might confound the spin-label oximetric measurements. © 1986 Academic Press, Inc.
81 citations
TL;DR: The 35 GHz ESR spectrum of frozen aqueous suspensions of synthetic melanin from autoxidation of dopa is asymmetric in the pH range 3-12, and the species present at high pH are suggested to be relatively localized radical anions, while the species detected at low pH are suggest to be protonated forms of the high pH species in which the unpaired electron is more extensively delocalized.
53 citations
TL;DR: In this article, the acid properties of NaHZSM-5 zeolites of various exchange degrees were studied by quantitative infrared (IR) studies of pyridine adsorption.
50 citations
TL;DR: In this paper, the dipole moments of 2-dimethylamino-6-propionylnaphthalene (PRODAN), a representative of a class of highly environment-sensitive fluorescent probes, were computed.
Abstract: MNDO geometry, CNDO/S CI spectra and dipole moments of 2-dimethylamino-6-propionylnaphthalene (PRODAN), a representative of a class of highly environment-sensitive fluorescent probes, were computed. Only the conformer with a twisted dimethylamino group has an excited state dipole moment high enough (27 D) to explain spectral properties of PRODAN. On the basis of the Amos—Burrows theory, fluorescence from the TICT state is predicted in polar solvents.
47 citations
TL;DR: It is shown that the fluorescence of multitryptophan-containing proteins, such as horse-liver alcohol dehydrogenase, 3-phosphoglycerate kinase and lysozyme, can be resolved for different segmental contributions, each characterized by collisional (Ki) and static (Vi) quenching constants.
Abstract: From acrylamide quenching results, analyzed by an itterative non-linear least-squares method, we have shown that the fluorescence of multitryptophan-containing proteins, such as horse-liver alcohol dehydrogenase, 3-phosphoglycerate kinase and lysozyme, can be resolved for different segmental contributions, each characterized by collisional (Ki) and static (Vi) quenching constants. The ability to resolve the heterogeneous fluorescence of proteins makes it possible to follow changes in dynamics of the individual residues. In yeast 3-phosphoglycerate kinase, which contains only two tryptophan residues, three fluorescent fractions, characterized by different accessibility to the quencher, were observed. Two of them are assigned to one of the tryptophan residue. This may be interpreted in terms of conformational fluctuations, which facilitate the access of acrylamide molecules to the buried tryptophan residues.
46 citations
TL;DR: The lungs of five species of European Anura and one species of Urodela have been studied by immunohistochemical methods to determine the occurrence, localization and distribution of serotonin, neuron-specific enolase, and eight regulatory peptides reported in the mammalian respiratory tract.
Abstract: The lungs of five species of European Anura and one species of Urodela (Triturus alpestris) have been studied by immunohistochemical methods to determine the occurrence, localization and distribution of serotonin, neuron-specific enolase, and eight regulatory peptides reported in the mammalian respiratory tract.
40 citations
TL;DR: The onset of puberty in bank vole females was studied, with uterine weight, ovarian weight, and the number of large ovarian follicles used as indicators of gonadal activity.
Abstract: The onset of puberty in bank vole females was studied, with uterine weight, ovarian weight, and the number of large ovarian follicles used as indicators of go nadal activity. Maturation of females born at the beginning of the reproductive season was suppressed by the presence of other females. Puberty of animals born at the end of season was primarily influenced by climatic variation.
TL;DR: In this article, the liver, femur bones, feathers and carcasses of birds collected in three polluted forest sites in southern Poland and in a relatively unpolluted site at Bialowiez Forest were determined.
TL;DR: The mobility of 5-doxyl stearic acid spin label (5-SASL) in the gel phase of dipalmitoylphosphatidylcholine membranes between the main transition and subtransition temperatures was studied as a function of cholesterol content.
TL;DR: Time-dependent analysis of nonstationary effects in velocity-selective optical pumping is performed with a four-level model for weak light intensities and the theoretical results are in a good qualitative agreement with the recent experimental observations.
Abstract: Time-dependent analysis of nonstationary effects in velocity-selective optical pumping is performed with a four-level model for weak light intensities. No phenomenological relaxation constants are introduced and the nonstationary effects are obtained as the consequence of averaging the time evolution of individual atoms in a vapor phase moving in the light fields when typical pumping times are comparable with the finite laser-beam transit times. Under appropriate conditions strong deformation of the population distribution of the long-lived lower state occurs, which in the case of polarization spectroscopy is responsible for the appearance of a dip (possibly narrower than the homogeneous linewidth) in the center of a Doppler-free resonance. The theoretical results are in a good qualitative agreement with the recent experimental observations.
TL;DR: In this paper, the postnatal changes in arrangement of the vascular system of the pia-arachnoid of rats are described based on scanning electron microscopy of microcorrosion casts and transmission electron microscope.
Abstract: The postnatal changes in arrangement of the vascular system of the pia-arachnoid of rats are described based on scanning electron microscopy of microcorrosion casts and transmission electron microscopy. At birth, the distal arteries and veins are embedded in a dense plexiform network of immature capillaries. Arteries and veins are interconnected by many small capillary anastomoses. The trunks are located above the pial plexus. The underlying plexiform vessels provide the matrix for the formation of additional collateral and precortical segments during further development. During the first postnatal week, the distal pial arteries and veins become visible as separate channels and emerge from the subjacent capillary plexus. The pattern of anastomosing arterial rings is now clearly visible. The pial arterial tree can be subdivided into conductive, collateral, and precortical distributive segments, according to Jokelainen et al. (1982). Subsequently, passive expansion of the vascular system takes place during the period of rapid brain growth. In young adults the majority of the formerly closed arterial rings are interrupted, possibly by regression of single collateral arterial segments (Fig. 6). The dense venous capillary plexus of the pia is maintained during the first eight days in spite of marked brain growth. The process of reduction of this capillary plexus starts at the arterial side and proceeds from proximal to distal segments of the veins during the second and third week. The capillary segments, which provide anastomosis between arterial and venous vessels, disappear at the same time as the regression of the dense venous capillary network.(ABSTRACT TRUNCATED AT 250 WORDS)
TL;DR: In this article, the authors search for axion events in the 3.59 MeV transition in 10B with a fourfold Mini-Orange spectrometer and no axion event was found within one percent of the prediction for the standard axion-to-γ-ray branching ratio.
TL;DR: In this paper, a model allowing to calculate the amount of Fe 3+ ions has been proposed; it assumes a fast electron exchange over iron atoms in octahedral sites between Fe 2+ and Fe 3+, which agrees very well with those obtained directly from the thermogravimetric analysis.
TL;DR: In this paper, the formation and structure of the vitelline envelopes in three species of mites, Euryparasitus emarginatus, Erythraeus phalangoides, and Hafenrefferia gilvipes (Oribatida), were studied.
Abstract: This communication presents results of studies on the formation and structure of the vitelline envelopes in three species of mites: Euryparasitus emarginatus (Gamasida), Erythraeus phalangoides (Actinedida), and Hafenrefferia gilvipes (Oribatida). In E. emarginatus and E. phalangoides, in which the oocytes are not covered with follicular cells, the material of the vitelline envelope appears first in vesicles under the surface of the oocytes prior to secretion by exocytosis. The formed vitelline envelope is built of a homogeneous material which is perforated by numerous channels containing oocyte microvilli. Later, as the microvilli are retracted, the channels disappear. In both of these species the formed vitelline envelope is incomplete and the micropylar orifice occurs as a transitional structure.
TL;DR: The lungs of Hyla arborea L. were examined by scanning and transmission electron microscopy and morphometric methods and found that the lining layer covering the internal lung surface contains numerous transformed LBs but tubular myelin figures are scarce.
Abstract: Lungs ofHyla arborea L. were examined by scanning and transmission electron microscopy and morphometric methods. The lungs contain several interconnected folds in a netlike reticular arrangement of first, second and third order, mainly covered with pneumocytes. On the septa of first and second order, irregularly distributed small patches of ciliated epithelium devoid of goblet cells are located. Dome-shaped neuroepithelial bodies can be seen in the vicinity of ciliated epithelium. The pulmonary epithelium consists of one type of pneumocyte, which contain in their cytoplasm three kinds of bodies: lamellar, dense and multivesicular. The dense bodies are precursors of lamellar bodies (LBs), while the multivesicular bodies are incorporated into the LBs, being later secreted to the air space. The lining layer covering the internal lung surface contains numerous transformed LBs but tubular myelin figures are scarce. The surface of the lining layer is coated by a thin film. The air-blood barrier, consisting of three layers: epithelium, interstitial space and endothelium, is 0.6 μm thick.
TL;DR: In this paper, the reaction of protonated 2,2′-bipyridine (bpy) with octacyanometalates (IV and V), [M(CN)8]n− (M = Mo or W, n = 3 or 4), gave the following complexes:
TL;DR: In this article, the authors present the results of Q.N.S. studies for two members of the homologous series of alkoxyazoxybenzenes, CnH2n+1O-ϕ-N2O-κ-OCnH 2n + 1; PAP (n = 2) and POAB (n= 3) measurements were performed on the non-deuteriated (d 0-PAP and d 0-POAB) and the chain deuteriated samples, d 10-Pap and d 14
Abstract: We present the results of Q.N.S. studies for two members of the homologous series of alkoxyazoxybenzenes, CnH2n+1O-ϕ-N2O-ϕ-OCnH2n+1; PAP (n = 2) and POAB (n = 3). The Q.N.S. measurements were performed on the non-deuteriated (d 0-PAP and d 0-POAB) and the chain deuteriated samples, d 10-PAP and d 14-POAB. Three models were fitted to the experimental data: (1) uniaxial rotational diffusion of the molecule around the axis with the smallest moment of inertia, (2) uniaxial rotational diffusion of the two moieties of the molecule around the N-ϕ bonds, (3) 180° instantaneous jumps of the two moieties of the molecule around N-ϕ bonds. We have assumed the molecule to exist in the trans conformation. The translational diffusion of the molecules and the methyl groups' reorientation were neglected. It turned out that model (3) does not describe the experimental data well. Models (1) and (2) describe the experimental data equally well, giving no preference for the axis of rotation. However, comparison of our...
TL;DR: An ascites subline (AA) of the murine sarcoma MC1M grows in vivo in the peritoneal cavity but dies in vitro when cultured on glass or collagen as discussed by the authors.
Abstract: An ascites subline (AA) of the murine sarcoma MC1M grows in vivo in the peritoneal cavity but dies in vitro when cultured on glass or collagen. The viability of AA cells in vitro is not influenced in cocultures with fibroblast cell line L929, and is diminished in cocultures supplemented with macrophage culture supernatant or in cocultures with non-adherent peritoneal cells. However, AA cells proliferate in vitro on glass or collagen when cocultured with syngeneic, semisyngeneic, and allogeneic peritoneal macrophages. This was demonstrated by tritiated thymidine incorporation assay, by AA cell number counting, and by measuring AA cell protein content. Proliferation also occurs when AA cells are separated from the macrophage monolayer by millipore filters.
TL;DR: It is concluded that repeated imipramine administration induces supersensitivity of hippocampal dopamine receptors and increased the number of slices sensitive to dopamine.
Abstract: The sensitivity of hippocampal neurons to dopamine was studied in hippocampal slices obtained from rats treated acutely (10 mg/kg) or repeatedly (10 mg/kg, 14 days, twice a day) with imipramine. In non-treated rats dopamine induced a slight excitation or depression of the firing rate of CA 1 pyramidal neurons in slice preparations. Hippocampal slices prepared from the imipramine-treated rats displayed greater changes in the firing rate after dopamine application. Repeated imipramine administration also increased the number of slices sensitive to dopamine. it is concluded that repeated imipramine administration induces supersensitivity of hippocampal dopamine receptors.
TL;DR: The base catalyzed isomerization of 2-(aroyl-methylene)-3-aryl-thiazolidine-4,5-dione derivatives leads to salts of 1-aryl, 3-aroyal-4-hydroxy-pyrroline-2-thio-5-one and aliphatic amines as mentioned in this paper.
Abstract: The base catalyzed isomerization of 2-(aroyl-methylene)-3-aryl-thiazolidine-4,5-dione derivatives1 leads to salts of 1-aryl-3-aroyl-4-hydroxy-pyrroline-2-thio-5-one and aliphatic amines2. It was found that2 undergo further transformation to 4-thioanilido-5-arylo-2,3-furanodione derivatives4. This series of reaction provides a convenient synthetic route to 2,3-furanodione derivatives4.
TL;DR: In this paper, the NH3 reorientations about Ni-N axes are observed in all three phases with an activation energy Ea ⋍ 2kJ/mol, and a discontinuity in the correlation times vs. inverse temperature at the phase I/phase II transition (140K) was observed.
Abstract: QNS measurements carried out on polycrystalline [Ni(NH3)6](BF4)2 revealed that the NH3 reorientations about Ni-N axes are occurring in all three phases with an activation energy Ea ⋍ 2kJ/mol. A discontinuity in the correlation times vs. inverse temperature at the phase I/phase II transition (140K) was observed. Two (extreme) models describing the stochastic NH3 reorientational motions were used to interpret the QNS spectra: the 120°-jumps and the uniaxial rotational diffusion. The quality of the fits for all spectra is quite good for both models, but according to the χ2 test, a small preference should be given to the 120°-jump model. Raman band shape measurements carried out on the same sample reveal BF-4 reorientations in phase I. These reorientations are abruptly stopped at the phase I/phase II transition.
TL;DR: In this paper, the rotational correlation time of the 4,4δ-di-n-alkoxyazoxybenzene homologous series was investigated for the isotropic and nematic phases and for 0.1 M solution in benzene.
Abstract: Far infrared spectra in the frequency range 20 to 200 cm−1 for the 4,4δ-di-n-alkoxyazoxybenzene homologous series are presented for the isotropic and nematic phases and for 0.1 M solution in benzene. In addition some partially deuteriated samples were studied. The spectra consist generally of two broad bands. By comparison of the spectra for different deuteriated compounds it is possible to interpret the higher frequency band as being connected with the intramolecular torsional vibration of the end groups. The band at lower frequencies we associate with the Poley absorption of librating molecules. The confined rotator model calculations performed for this band, for all compounds studied, give the rotational correlation time which is in good agreement with the correlation times as derived from quasi-elastic neutron scattering experiments.
TL;DR: In this article, the tautomerism of 2,4-dihydroxyquinoline in the gas phase is discussed in terms of its electron impact fragmentation pattern and of quantum chemical calculations by the LCAO-MO method in the CNDO/2 approximation.
TL;DR: In this article, the alkylidenemalononitrile dimers reacted smoothly with trifluoromethanesulfenyl chloride to yield 1-amino-2,2,6- tricyano-3,3-alkyl-5 [(trifluorsomethylthio)alkyl] -1, 3-cyclohexadienes 5 − 7 and 9.