Genomic fingerprinting: new possibilities in determining the species identity of Brucella

The genomes of various Brucella species were shown to contain hypervariable sequences which can be detected by the M13 DNA. It has been demonstrated that the method of DNA fingerprinting opens up new possibilities in differentiation and identification of Brucellosis agents.     

Karyological characteristics of a new continuous cell line of human hypernephroma

A new stable human hypernephroma cell line has been characterized by differential staining R-, C- and Ag-I-techniques. The karyotype of the cultivated hypernephroma cells has been designed using the statistical analysis and karyotype reconstruction methods. The specific chromosomal markers of the cell line are described.     

Effects of gastric mucosa irradiation with helium-neon laser on epithelial cells

Effect of various doses of low-tense laser irradiation on proliferative and functional morphology of fundal gastric epitheliocytes in rats was studied by endogastric irradiation with the methods of histochemistry, autoradiography, transmission and scanning electron microscopy. It was shown that laser irradiation effect varied with its dose and was spread on gastric mucosa lying at the site of direct influence. The doses of irradiation that had no alternative effect induced reconstruction of epitheliocytes especially mucocytes indicating intensification of specific function in them, as well as an increase of proliferative activity.     

Interferon-specific cellular receptors in cultured human cells, differing in sensitivity to alpha-interferon

The interferon-specific cellular receptors in human cells cultures differing in sensitivity to alpha-interferon have been studied. The J-41 cells resistant to alpha-interferon are practically devoid of receptors highly specific to alpha-interferon. The coefficient of equilibrium and the number of receptors analyzed after Scatchard for J-96 culture of cells are 15.6 x 10(11) M-1 and 210 +/- 90, respectively. Evidently, resistance of J-41 cells to alpha-interferon is connected with the absence of interferon receptors and, as a consequence, inability to interferon-receptor interaction.     

Biological diversity and the community structure of organisms

Biological diversity and the complexity of the community structure of benthic animals in different bodies of water are evaluated using the Shannon index. The literature data on the communities in Lake Krasnoye (Karelian Isthmus, Leningrad Oblast), Shchuchy Bay of Lake Ladoga, Neva Bay, and the eastern part of the Gulf of Finland have been analyzed. The extrema (maxima and minima) and the inflection point of the curve of functions are determined with the help of derivatives. The rate of the secondary succession is evaluated for the first time by the example of benthic communities. It is shown that the community structure of bottom animals in the Shchuchy Bay ecosystem formed in the process of succession proves to be more complex than in Lake Krasnoye and the Neva Bay communities that have been formed for a long time. Communities of bottom animals are less complex in polluted waters of the top of the eastern part of the Gulf of Finland. It has taken 12 years to reach the maximum diversity of the bottom animal communities in Shchuchy Bay, 16 years in Lake Krasnoye, and 7–10 years in Neva Bay. It is supposed that, under favorable conditions in the waterbodies of a moderate climate and in the absence of heavy pollution or eutrophication, it takes 12–14 years on average to form the most complex community structure of bottom animals (3–4 bit/spec.). The structure of communities in polluted waters remains simple.