Isolation of cobalt-resistant strains of propionic acid bacteria, potent producers of vitamin B12

A method of adaptation to cobalt nitrate at high concentrations allowed us to isolate 46 strains of propionic acid bacteria Propionibacterium acidipropionici, resistant to excessive amounts of Co2+ in the medium. Studies of these strains revealed cultures that were most potent in synthesizing vitamin B12. The yield of vitamin B12 was increased 3 times, compared to parent strains.     

A case of deletion of the short arm of the chromosome 21 (21p-) (christchurch chromosome) discovered prenatally:clinical and cytogenetic data

Results of cytogenetic research of placental villi and amniotic fluid cells culture of the 22-weeks-old fetus with multiple congenital malformations (MCM) are presented. The absence of the short arm in one of the homologue of the chromosome 21 was revealed. Cytogenetic analysis of the fetus father's blood lymphocytes determined the similar chromosome. Further research of the father's karyotype made by FISH-method using specific DNA samples had discovered the absence of subtelomeric parts in the short arm of the chromosome 21 that might be considered as a deletion. It was suggested that the effect of position and interaction of genes could play a key role in appearing of MCM in the fetus in the case when the 21p-chromosome was transferred to it from the healthy parents.     

Using method of DNA microelectrophoresis for the assessment of genotoxic effects of mutagens in cultured human hemopoietic cells

Formation of single- and double strand breaks in DNA which may be discovered by microelectrophoresis in agarose gel is one of the criterion of genetical lesions in cells as a result of apoptosis or of genotoxic agent action. Genotoxic action of nickel chloride at the level of DNA of the individual cells in the initial culture of human embryonic haemopoietic cells was studied. It has been shown that about 2% cells in the studied in vitro populations were in the apoptosis state. Nickel chloride induced increasing of the frequency of formation of electrophoretic tracks of "comet" type with destroyed DNA.     

Cytomorphological characteristics of normal lymphatic gland cell structure

Numerical and qualitative characteristics of cell structure of 87 normal human lymphatic gland cytograms of various age groups have been studied. For each age group distinctive cell profiles of cytograms were established and cytological features of their development and involution have been determined.     

Genetic structure of crucian carp (Cypriniformes, Cyprinidae, Carassius L. 1758) populations of middle-Dnieper basin

Comparative analysis of Middle Dnieper crucian carp's population structure was made by means of biochemical gene marking, cytometry and biological analysis. As a result the structure was found, which may by expounded like association of the genetically related species and forms. This association consists of diploid C. auratus (which predominates in population), C. carassius (which was found in the some of north-eastern reservoirs only) and triploid C. gibelio. In Ukraine the homogeneous populations of C. gibelio can be found on the north-east of Eastern Ukraine only. Though some of individuals maybe present with diploid C. auratus. Besides were found hybrid form: diploid C. auratus-C. carassius and presumably tetraploid C. auratus-C. gibelio and C. gibelio-C. carassius. However in the tetraploid's spectra were absent a number of specific alleles, that marking C. species-one of the parental species of triploid C. gibelio. Therefore presumptive tetraploids have not difference from C. auratus and diploid C. auratus-C. carassius on the gene markers level. Nevertheless they are neatly diagnose by the erythrocytes which have good difference and are bigger then diploid species erythrocytes in 40% (C. auratus-C. gibelio) and 100% (C. gibelio-C. carassius).     

Mutation variability and marker trait inheritance in hybrid-mutant populations F2M2 of winter wheat

Influence of hybrid seed treatment with mutagenes on genetic variability in hybrid populations of the second generation of winter wheat has been investigated. Treatment with mutagenes in moderate doses results in deviation of segregation of marker traits as compared to control towards either increase or decrease of the ratio of recessive allels. It was shown that in crossing combinations with red-ear form as one of the parental components, treatment with gamma rays at the dose of 100 Gy leads to significantly larger deviations of disintegration comparing to control.     

Use of ISSR-markers for determination of convergent evolutionary relations in Fagus genus

Genetic relationships between members of Fagus genus were assessed using ISSR markers and amplification. The taxonomic status of Fagus sylvatica L. and Fagus orientalis LYPSKY. species in Ukraine has been ascertained more precisely. Intraspecies mean genetic distances were compared according to Nei & Li and respective dendrogram was constructed with the complete joining method.     

To the ways of the most reasonable implementation of digital radiography into the practical public health of the Russian Federation

The main idea of the authors' paper is to propose the most reasonable way of actively introducing the digital principle into the traditional roentgenological section of radiation diagnosis. For this, a luminophore digital radiography system has been chosen. The authors of the paper give a full-scale assessment and appropriate recommendations for its use. The paper essentially discusses the entire complex of matters that permit assessment whether its sound use is possible in regional and municipal health care systems. This is both a section devoted to a dose load, by making a comparative assessment of luminophore radiography and "the green system" and a study of different clinical diseases (456 cases). In their study, the authors have applied an original principle in the formation of an image obtained and some other approaches in order to make a comprehensive assessment of this method. In the authors' opinion, luminophore radiography has a variety of advantages. Firstly, this technique can be simultaneously applied to several nondigital apparatuses, including those available in the ward and it shows a rather diagnostic effectiveness and economic profitability, yields a qualitative image of varying density tissues upon single exposure, and has some other capacities of the CR system as a digital technique. All this things considered, the authors consider that luminophore radiography may be one of the main ways of introducing a digital technique into the conventional roentgenological section of radiation diagnosis at the level of regional and municipal heath care systems.     

Structural and functional characterization of cyst cells in Sarcocystis sp. (Sporozoa, Apicomplexa)

By means of light and electron microscopy, the structural pattern of muscle cysts (sarcocysts) was examined for the four species of the genus Sarcocystis: S. muris (from murine skeletal muscles), Sarcocystis sp. and S. fusiformis (from, respectively, heart and skeletal muscles of buffalo), and S. ovifelis (from ovine tong muscles). The orderly fashion of the interior of the cyst is attained by partitition of its space into numerous compartments with the involvement of the intermediate filaments. These, in their turn, are bound to each other by thin filaments to make eventually a common filamentous net. The net limits separate groups of cells referred to as cyst zoites. The common net of filaments and microtubules (when present) may be regarded not only as the organizer of the cyst interior cytoskeleton, but also as the main mechanism of substance transportation in various directions: from the host cell to the sarcocyst, and within or outside the cyst. The role of dedifferentiation, proliferation and differentiation processes is suggested in the establishment of the fixed sequence of events throughout the unidirectional development of cyst cells and their interaction, from precystic meronts to cyst merozoites (gamonts). Special attention is paid to metrocyte morphogenesis and functioning. In the present work, metrocytes subjected to apoptosis were recognized. It is suggested that phenomenon of programmed cell death in metrocytes may be associated with the control of cell number in mature and ageing sarcocysts.     

Protein synthesis-dependent reactivation of environmental conditioned reflex in terrestrial snails

We investigated influence of anisomycine injection on reconsolidation of contextual memory after development of environmental conditioned reflex in terrestrial snail Helix. Testing the amplitude of behavioral reactions (tentacle withdrawal) in response to standard tactile stimulation of the skin in two contexts: a) when the snail was fixed by the shell and was moving on the surface of the ball floating in water, or b) was moving on the flat surface of glass terrarium, has shown no difference in response amplitudes. After a session of electric shocks (5 days) in one context only (ball) the associative learning was clearly observed as the significant difference of response amplitudes in two contexts. On the other day following testing was performed a session of "reminding", immediately after which the snails were injected by anisomycine (control snails were injected by saline solution). Testing has shown that injection of anisomycine led to impairment of the context conditioning. Results suggest that the mechanisms of consolidation of new memory and memory reconsolidation after retrieval are not identical.