Localization of the antigenic determinants in carcinoembryonic antigen: the role of the carbohydrate component

The majority of topographic antigenic determinants of the carcinoembryonic antigen (CEA) representing a glycoprotein were shown to contain sugar residues of the CEA carbohydrate chains. Periodate oxidation of CEA followed by reduction afforded a corresponding CEA derivate (CEA-POR), which retained 3% antigenic activity of CEA. In secondary and tertiary structures CEA-POR was proved to be close to CEA pre heated to 80 degrees C. Formation of borate complexes with sugar residues of CEA decreased the CEA antigenic activity to 5% while a but did not affect the spatial structure of its protein core.     

Role of a carbohydrate component in the formation of immunochemical determinants of carcinoembryonic antigen

Carcinoembryonic antigen (CEA) isolated from metastases of colon adenocarcinoma was subjected to deglycosylation with liquid hydrogen fluoride. The protein fraction obtained (PF CEA) was used for to prepare monospecific antiserum to PF CEA. Comparative studies of CEA, PF CEA, and non-specific cross-reacting antigen (NCA-1) have been carried out using monospecific antisera. Circular dichroism spectra of CEA and PF CEA have been studied. The data obtained suggest that some immunodominant regions of CEA are topographic, and their formation needs a specific conformation of the macromolecule, which is stabilized by the sugar moiety.     

Genetic diversity and phylogenetic relationships in the zokor subfamily myospalacinae (Rodentia,Muridae) inferred from RAPD-PCR

Zokors (Myospalacinae) is a group of rodents specialized for underground life, endemics of eastern Asia, which is taxonomically and evolutionarily poorly studied. We examined genetic diversity and phylogenetic relationships among zokors (Myospalax myospalax, Myospalax aspalax, Myospalax armandii, Myospalax psilurus, Myospalax smithii) using RAPD-PCR. The subfamily Myospalacinae was shown to be monophyletic and contain four evolutionary branches: M. myospalax, M. aspalax-M. armandii, M. smithii and M. psilurus. Genetic differences and high differentiation were found among the species and between two geographic forms of Manchurian zokor M. psilurus from the marginal parts of the range, Transbaikalia and Primorye. The psiluris phylogroup was shown to be dichotomically divided into two clades according to the geographical distribution of animals from Transbaikalia and Primorye. The genetic differentiation between the geographic forms of M. psilurus corresponded to the differentiation between morphologically similar species M. aspalax and M. armandii. M. armandii is a sister taxon with regard to M. aspalax. This new evidence on the evolutionary relationships among zokors does not contradict the traditional views inferred from morphological, karyological, and allozyme data, on apartness of M. myospalax and the character of evolution in this group. The species status of Myospalax psilurus Milne-Edwards, 1874, M. epsilanus Thomas, 1912, and M. armandii Milne-Edwards, 1867, which had been suggested earlier on the basis of biochemical and karyological data, was confirmed.     

Substantia nigra neurons activity in cat brain during realization of self-initiation of behavioural action

Activity of 50 dopamine and 67 non-dopamine neurons was studied during motivated behavioural actions in the cat brain black substance. 66% of former and 88% of latter neurons modified their activity before and during autoinitiated voluntary movements. The data obtained suggest that dopamine neurons are involved in organisation of movements in behavioural actions with cognitive components.     

Study of axodendritic synapses of the hippocampal CA3 field in experimental uremia and administration of exogenous parathyroid hormone]

The effect of parathyroid hormone intraperitoneal injection at different stages of experimental uremia induced by subtotal nephrectomy on ultrastructural morphofunctional characteristics of hippocampus Ca3 field axospinal synapses was studied. A conclusion is made that the decrease of synaptic activity in the hippocampus field due to redistribution of calcium ions between spine cytoplasm and spine apparatus may take place after PTH injection and during uremia development.     

Binuclear manganese(III) complexes of an unsymmetric pyrazolate-based compartmental ligand with hard donor set

The synthesis, crystal structure and magnetic properties of manganese(III) binuclear complexes [Mn^III₂(L-3Н)₂(CH₃ОH)₄]·2CH₃ОH (1) and [Mn^III₂(L-3Н)₂(Py)₄]·2Py (2) (L = 3-[(1E)-N-hydroxyethanimidoyl]-4-methyl-1H-pyrazole-5-carboxylic acid) are reported. The ligand contains two distinct donor compartments formed by the pyrazolate-N and the oxime or the carboxylic groups. The complexes were characterized by X-ray single crystal diffraction, revealing that both 1 and 2 consist of dinuclear units in which the two metal ions are linked by double pyrazolate bridges with a planar {Mn₂N₄} core. Cryomagnetic measurements show antiferromagnetic interaction with g = 1.99, J = −3.6 cm⁻¹, Θ = −2.02 K for 1 and g = 2.00, J = −3.7 cm⁻¹, Θ = 1.43 K for 2.     

Properties of the EEG μ rhythm and its reactivity during the performance,observation, imitation,and auditory recognition of movements in children aged 4–14 years

We studied the frequency and amplitude properties of the EEG μ rhythm in children (n = 38) aged 4–14 years under the condition of visual fixation (VF) on a video image of a computer mouse, as well as the parameters of its desynchronization during the tasks involving self-controlled performance, observation, imitation, and auditory recognition of the hand circular movements (SPM, OM, IM, and ARM, respectively) with a computer mouse. We observed age-related increment in the modal frequency of μ rhythm in loci C ₃ and C _z. During the SPM process, a significant decrease in the amplitude of μ rhythm was found in loci C ₃ (26.7%) and C _z (10.3%); during the OM, in locus C _z only (9.9%). The effects of the μ rhythm desynchronization during both self-paced and observed movements might be an evidence of well-developed neural matching mechanisms that provide the processes of performing and observing similar actions in children aged 4 to 14 years. During the IM, the desynchronization of μ rhythm was significant in loci C ₃ (27.4%) and C _z (15.3%). We hypothesize that the statistically significant increase (from SPM to IM) in the depression of μ rhythm in locus C _z is likely to be an effect of a social gaming context common for the situations when children imitate the movements of adults. The index of desynchronization of μ rhythm under the studied conditions did not depend on the age of children. Possible relations of identified modulations of the μ rhythm to the activity of the mirror neuron system were also discussed.