Participation of Free-Radical Processes in Structural and Metabolic Disturbances in the Lung Tissues Caused by Exposure to Coal-Rock Dust and their Adaptogenic Correction.

Adaptive correction of structural and metabolic disturbances in the lungs caused by longterm exposure to coal-rock dust were studied in experiments on rats. It was shown that the complex antioxidant preparation containing dihydroquercetin compensated disturbances in the redox balance in the lung tissue, prevented the formation of dust granulomas, and reduced the severity of degenerative changes in the bronchopulmonary system.

Experimental Study of the Mechanisms of Intracellular Defense in Cardiomyocytes Associated with Stages of Anthracosilicosis Development.

Mechanisms of intracellular defense of rat cardiomyocytes were studied in dynamics of anthracosilicosis development induced by long-term inhalation of coal and rock dust. It was shown that synthesis of transcription factor HIF-1α and protective proteins increased in the heart at the early stages of coal and rock dust inhalation (1-3 weeks), and these changes limited the development of free radical oxidation and activated metabolism of glucose and fatty acids. Exposure to coal and rock dust for 6-12 weeks activated free radical oxidation and decreased basal metabolism in cardiomyocytes.

[Development of radioadaptive properties for microscopic fungi, long time located on terrains with a heightened background radiation after emergency on Chernobyl NPP].

In 7 species of micromycetes which were isolated from radioactive contaminated areas of Chernobyl NPP zone under exposure of two artificial sources: y-low energy (121Sn) and radiation mix type gamma + beta (137Cs). Two new earlier unknown radioadaptive properties for fungi--radiotropism and radiostimulation were established. The strains, which were isolated from clean areas, did not have such features. All investigated strains, which have shown positive radiotropism at the same time, have shown stimulation of conidia germination and of length of the emergent hyphum under exposure to one of sources of radiation. It was shown that micro fungi having radioadaptive properties, the adaptive response to high (100-1000 Gy) ionizing radiation doses was found that is evidence of that these strains have high radio resistance level. Nevertheless fungal strains have shown varied response to presence of ionizing radiation depending on its type and absorbed dose.

Comparative responses of microscopic fungi to ionizing radiation and light.

Microscopic fungi of 47 species and 24 genera isolated from radioactive soil and other radioactive substrates of a 10-km alienation zone from Chernobyl Nuclear Power Plant were investigated. Only 19 % of such fungi showed toward the ionizing irradiation source positive radiotropism. Strains with best-defended radiotropism responded to the influence of weak white light. Both of these responses (radiotropism and photostimulation) were of an adaptive nature, were found in both dark-colored and light-colored micromycetes and were probably a strain-related feature.

[Peculiarities of growth and development of strains Hormoconis resinae (Lindau) V. arx & De Vries F. Resinae and Cladosporium sphaerospermum penz].

The work deals with the effect of limitation of organic carbon (glucose) on the growth and morphology of two species of microscopic fungi Hormoconis resinae and Cladosporium sphaerospermum (11 strains), isolated from premises of the 4th unit of the Chernobyl NPP and isolation places which arc pure from radionuclides. The dissimilar reaction of each of the species to decreasing the amount of organic carbon in the culture medium has been established. Ontogenesis reduction was observed for both species under the conditions of limitations of organic carbon. In was manifested for H. resinae in reduction of the typical conidial sporulation and in transition to micelial way of existence, and only conidial sporulation and formation of "empty" micelium Were registered under such conditions for C. sphaerospermum. The studied strains were related to 3 ecologic groups by oligocarbotolerance criterion: typical saprotrophs, intermediate group, strains with a tendency to oligocarbotolerance.

[Growth and development peculiarities of Hormoconis resinae (Lindau) von Arx & de Vries strains isolated from premises of the 4th unit of the Chernobyl NPP].

Growth characteristics of Hormoconis resinae (Lindau) von Arx & de Vries, isolated from premises of the 4th unit of the Chernobyl NPP were studied on solid and liquid media. Radial growth rate of the studied strains varied from 0.05 to 0.08 mm an hour and did not depend on radioactivity of isolation place and composition of the nutrient medium. Index of substrate I colonizing intensity has demonstrated that all studied strains grew better on nutrient-rich medium. Morphological changes in studied strains on starving nutrient-poor media showed a decrease of biomass accumulation, reduction of sporogenesis, inhibition of micelial growth. Concerning both characteristic of biomass accumulation and morphological changes, all studied strains were referred to 3 groups: (1) heterotrophic strains, (2) strains with a tendency to oligocarbotolerance, (3) strains of intermediate group.

[Survivability of some black yeast-like fungal species under UV-irradiation]. / Vyzhivaemost' nekotorykh vidov chernykh drozhzhepodobnykh gribov pri vozdeistvii UF-luchei.

The survival of 4 species (14 strains) of black-pigmented yeast-like fungi, isolated from radioactive polluted ecotopes, after UV-irradiation has been studied. Their survival was different in the limits of 3 orders from 0.7 to 0.0001% and was described by the exponential composite exponential and composite sigmoid types of dose curves. Essential heterogeneity for the level and character of survival after UV-irradiation of conidia Aureobasidium pullulans, Hormonema dematioides, Exophiala cf. jeanselmei and Exophiala sp. has been presented.

Accumulation of radionuclides from radioactive substrata by some micromycetes.

Overgrowing (interaction) and dissolution of intact and milled hot particles by various micromycetes were studied under laboratory conditions. Hot particles used for the investigation originated from the Chernobyl accident release and atomic bomb testing sites. The micromycetes investigated were mitosporic fungi mainly isolated from the Chernobyl site and vicinity. Most of the fungal species and strains showed a tendency to grow towards the hot particle, overgrow it and dissolve it after prolonged contact. The accumulation (absorption and adsorption) of radionuclides from intact hot particles was generally more intensive for (152)Eu than for (137)Cs by a factor of about 2.6-134, while in experiments with milled samples the (152)Eu and (137)Cs accumulation was similar, except for some fungal species, which showed higher (152)Eu than (137)Cs sorption. It could be shown that the main factors influencing Cs and Eu accumulation in fungi are: fungal species and strains and the size and composition of the hot particle.

[Comparative estimation of biocides and crown-ethers effect on micromycete-destructors cultures]. / Sravnitel'naia otsenka vliianiia biotsidov i kraun-éfirov na kul'tury mikromitsetov-destruktorov.

Influence of catamine AB, catapine, macrocyclic polyethers (crown-ethers [15]C-5, B[15]C-5, [18]C-6, B[18]C-6, DCH[18]C-6, DA[18]C-6) and mixtures of catapine with crown-ethers on fungal test-cultures of Aspergillus sydowii (Bain. et Sart.) Thom et Church, Cladosporium cladosporioides (Fr.) de Vries and Penicillium tardum Thom. It is shown, that solutions of catamine AB show the inhibiting effect in concentrations which are one level lower than in catapine. Inhibition influence on the growth of fungal test-cultures is found to be higher for crown-ethers B[15]C-5 and B[18]C-6 in contrast to [15]C-5 and [18]C-6 (B[15]C-5 > [15]C-5; B[18]C-6 > [18]C-6). Synergism of inhibition influence of catapine-bactericide and crown-ethers in the mixture on fungal cultures is established in contrast to influence of separate components of the mentioned substances.

[Comparative analysis of radial linear growth velocity of micromycetes isolated from different ecotopes]. / Sravnitel'nyi analiz skorosti radial'nogo rosta mikromitsetov, vydelennykh iz razlichnykh ékotopov.

The work aim was the discovering of peculiarities of microscopic fungi responding to radioactive pollution by growth velocity change. The linear growth velocity of a broad range of micromycetes was analyzed. They were chosen in such a way that every species, as far as possible, was presented by the strains isolated from radioactive polluted and clean regions. Most of the studied species were characterized by the absence of reliable growth velocity differences of strains of the same species growing on rich and starving media. Only two species--Aureobasidium pullulans and Penicillium spinulosum were the exception. Their growth velocities on malt-agar were much more then those on starving medium (1.7-3.6. times). Species Hormonema dematioides did not have reliable differences of growth velocity on optimal and starving media, but A. pullulans had this difference (2.3-3.6 times). It is supposed to use this observation to simplify identification of these species. Only strains within species Cladosporium sphaerospermum and especially P. funiculosum isolated from radioactive polluted ecotopes had growth velocity which was less then that of the strains from clean regions. The delay of growth velocity in such conditions can testify to adaptive change of metabolic processes of these strains. The strains which were characterized by delay of growth velocity existed at the substrates with high radioactive pollution for a long time.

[Destruction of radioactive particles by strains of Cladosporium cladosporoides (FRES.) de Vries]. / Destruktsiia radioaktivnykh chastits shtammami Cladosporium cladosporoides (Fres.) de Vries.

Reactions on the ionizing radiation of 14 Cladosporium cladosporioides strains were studied. Only 5 of them displayed radiotropizm. The ability of C. cladosporioides strains 4 and 5 with positive radiotropizm and museum C. cladosporioides strain 396 and its alb-mutant SM without positive radiotropizm to destruct radioactive particles of Chernobyl and explosion origin was studied. Two ways of radioactive particles destruction by C. cladosporioides were established, one of them is a direct way by fungal overgrowth of hot particles and the second one an indirect way only by fungal metabolites. Mycelium of the studied C. cladosporioides strains sorbed radionuclides from radioactive particles during cultivation on the liquid and agarized media. No certain inclinations of the individual strains to accumulation of radionuclides 137Cs or 152Eu were ascertained.

[Peculiarities of linear growth of the melanin-containing fungi Cladosporium sphaerospermum Penz. and Alternaria alternata (Fr.) Keissler]. / Osobennosti lineinogo rosta melaninsoderzhashchikh gribov Cladosporium sphaerospermum Penz. i Alternaria alternata (Fr.) Keissler.

Results on determination of radial (linear) growth rate of melanin-containing fungi Cladosporium sphaerospermum Penz. and Alternaria alternata (Fr.) Keissler concerning place of their isolation and ecologic peculiarities are presented in the paper. Essential differences, as to all studied indices of the strains of C. sphaerospermum strains, isolated from premices of the ChNPP 4th unit from the control strains of this species have been established. Only strain 34 of C. sphaerospermum, isolated from the cable driving region of the "Shelter" object, which did not differ from the control strains as to all the studied indices, made the exception. The radial growth rate was 2-4 times as low and variability amplitude 10-30 times as high in strains 60 and 5-1 of C. sphaerospermum, (which suffered high radiation load), as in the control strains of this species. The radial growth rate of C. sphaerospermum studied strains was an order lower as a whole than that of A. alternata strains. All the above said evidence for implementation of K-type vital strategy by C. sphaerospermum species and in this connection one can suppose its active growth on the surface of walls and ferroconcrete structures of the ChNPP 4th unit. Absence of differences, as to the studied radial growth indices, between A. alternata strains isolated from the ChNPP 4th unit premices and control strains of the species can evidence for the existence of A. alternata species under the conditions of high radioactivity in the surviving state.

Intraspecific variation in gamma-radiation resistance and genomic structure in the filamentous fungus Alternaria alternata: a case study of strains inhabiting Chernobyl reactor no. 4.

This is probably the first report on intraspecific variation in radiation resistance for filamentous fungi. It was revealed that natural ("field") strains of the filamentous fungus Alternaria alternata are extremely variable in response to gamma-irradiation ranging from supersensitive to highly resistant to radiation. At the same time nearly all strains originating from the highly radiation-polluted reactor of the Chernobyl (Ukraine) Nuclear Power Plant possessed high radiation resistance. The genome structure of strains studied by universally primed polymerase chain reaction (UP-PCR) was found to be well conserved in "reactor" but not in "control" strains. The "reactor" strains appear to be genetically adapted to this high radiation habitat by means of selection, thus providing a natural source of genetically homogeneous fungal lineages.

[Screening of alpha-N-acetylgalactosaminidase producers among microorganisms of different taxonomic groups]. / Skrining produtsentof al'fa-N-atsetilgalaktozaminidazy sredi mikroorganizmov razlichnykh taksonomicheskikh grupp.

Screening of producers of alpha-N-acetylgalactosaminidase among 854 strains of micromycetes, 171 yeast and 357 bacterial cultures has been carried out. A capacity to synthesize the enzyme was revealed in 11% of cultures. Representatives of Aspergillus genus (activity--0.11-0.142 un./ml) were most active in producing the enzyme. It has been established that glucosidases spectrum in the culture liquid of 18 most active strains was characterized by complete homogeneity and by the presence of a rather high level (0.5-0.9 un./ml) of alpha-galactosidase activity. Complex preparations of alpha-N-acetylgalactosaminidase and alpha-galactosidase have been obtained from the culture liquid of producers by fractionation by ammonium sulphate (30 and 90% saturation); their pH- and thermo-optimum, pH- and thermal stability have been studied. It was shown possibility to induce alpha-N-acetylgalactosaminidase synthesis by a number of carbohydrates (galactose, glucose, galactosamine, and glucosamine), complex-forming substances (guanidine HCl), nitroaminoguanidin and guanidine carbonate and bovine blood. As a result the strain of Aspergillus niger 185 III was chosen which activity level could be increased more than 3 times (activity--0.6 un./ml as compared to initial one).

[Statistical criterium of pollution heterogeneity in the research of biotic factors of radionuclides migration]. / Statisticheskii kriterii geterogennosti zagriazneniia pri issledovanii bioticheskikh faktorov migratsii radionuklidov.

The nature of the radionuclide contamination resulting from Chernobyl disaster is in its spatial and aggregate heterogeneity determined by the interaction of systematic and incidental factors. To study the radionuclide migration in the soil-plant system, an independent statistical index of contamination heterogeneity H = RAsAp is proposed which is calculated as a Brave-Pirsens coefficient of linear correlation between radioactivity of soil and dry biomass of plants grown on it and which allows to determine relative range of contamination that appears in the form of "hot particles". An adequacy of this index is substantiated, and it is used to analyze the experimental results on radionuclide migration.

[The dynamics of the fungal mycelial content in the soils of stationary posts in a 30-kilometer zone around the Chernobyl Atomic Electric Power Station]. / Dinamika soderzhaniia gribnogo mitseliia v pochvakh statsionarov 30-kilometrovoi zony ChAES.

The paper deals with mycobiota of radionuclide-polluted soils of seven stationary posts in the 30-kilometer zone of the Chernobyl NPP and one in the vicinities of Kiev (Feofaniia). The lengths of light-and dark-coloured fungal mycelium were determined in the soil under study by the method of membrane filters for 1987-1989. Data obtained have been analyzed with the account of the radioactivity level of the soil samples, season and depth of the sampling horizon. The dynamics of mycelium content in soils has been traced which evidences for its seasonal changes and prevalence of dark-pigmented mycelium at the beginning which then was changed by predominance of light-coloured mycelium. It is supposed that radioactive contamination of soil is one of considerable components of the whole complex of ecological factors which determine the dynamics of fungal mycelium content in soil.

[Complexes of soil micromycetes in the area of the influence of the Chernobyl Atomic Electric Power Station]. / Kompleksy pochvennykh mikrokitsetov v zone vliianiia Chernobyl'skoi AES.

Complexes of soil micromycetes in the Chernobyl 30-km zone of the Ukrainian Polesye were studied for 1986-1989 with regard for such ecological parameters as the level of radiation contamination, a particular observation site, depth of soil horizon and season. As a result of the study correlation pleiads of soil micromycete complexes have been revealed with their structure and fungal genera characteristic of such complexes determined. The overwhelming majority of correlation pleiads of fungal complexes are attributed to complex-organized ones and this indicated high radioresistance of mycobiota in the studied, soils. Melanine-containing genera of fungi rank among the first in formation of correlation pleiads of soil micromycete complexes.