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S. T. Zakhidov T. L. Marshak E. A. Malolina A. Yu. Kulibin I.A. Zelenina S. M. Pavluchenkova V. M. Rudoi O. V. Dement’eva S. G. Skuridin Yu. M. Evdokimov 《Biochemistry (Moscow) Supplemental Series A: Membrane and Cell Biology》2010,4(3):293-296
The effect of gold nanoparticles on mouse epididymal sperm has been studied using the model system of nuclear chromatin decondensation
in vitro. It is shown that the treatment of gametes, preliminary membrane-freed by sodium dodecyl sulfate, in the mediums
containing gold nanoparticles (with diameter ∼2.5 nm) in concentrations 1.0 × 1015 or 0.5 × 1015 particles/ml and following incubation in dithiothreitol solution (DTT) resulted in failure of chromatin decondensation process
and nucleus structure. We conclude that gold nanoparticles possess spermatotoxicity. The mechanism of cytotoxic effect of
gold nanoparticles may be related with their interaction with molecules of double-helix DNA. The model system studied in this
research is applicable for further investigations of cytotoxic effects of nanoparticles of different origin and made of different
metals. 相似文献
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4.
The viability of three species of Fusarium pathogenic to winter cereals was differently affected by temperature. F. culmorum survived in vitro in soil for 4 months at 8, 20 and 30 °C, the number of colony forming units (CFU) recorded at these temperatures after incubation being 125, 185 and 624 % respectively when compared with the number present at the beginning of the experiment. F. avenaceum and F. heterosporum barely survived at 8 °C after incubation for 4 months but at 20 °C the numbers of CFU were 314 and 380 % respectively, while at 30 °C the corresponding number tor each of these species was 200 %.
At natural soil temperatures in winter, the number of CFU of F. culmorum after 4.5 months decreased to 60, 70 and 87 % of the number present at the beginning of this experiment when infested soil was buried at depths of 7–10, 15—20 and 30 cm respectively. In the upper soil layer where winter temperatures were lowest, survival of F. avenaceum and F. heterosporum did not occur. Survival rates for these two species at a depth of 15—20 cm were 20 and 5 % respectively. In the deepest layer of soil (30 cm) survival of these two species was 30 % for F. avenaceum and 10 % for F. heterosporum of the number present at the beginning of this experiment.
These results demonstrate that during the early spring stages of growth of winter wheat, inoculum of F. culmorum , unlike that of F. avenaceum and F. heterosporum , is also a source of infection in the top soil layer in our climatic conditions. 相似文献
At natural soil temperatures in winter, the number of CFU of F. culmorum after 4.5 months decreased to 60, 70 and 87 % of the number present at the beginning of this experiment when infested soil was buried at depths of 7–10, 15—20 and 30 cm respectively. In the upper soil layer where winter temperatures were lowest, survival of F. avenaceum and F. heterosporum did not occur. Survival rates for these two species at a depth of 15—20 cm were 20 and 5 % respectively. In the deepest layer of soil (30 cm) survival of these two species was 30 % for F. avenaceum and 10 % for F. heterosporum of the number present at the beginning of this experiment.
These results demonstrate that during the early spring stages of growth of winter wheat, inoculum of F. culmorum , unlike that of F. avenaceum and F. heterosporum , is also a source of infection in the top soil layer in our climatic conditions. 相似文献
5.
Anna Stepanova Maria Malunova Svetlana Salamaikina Renat Selimov Aleksandra Solov’eva 《Phyton》2021,90(2):543-552
Rhodiola quadrifida is a rare mountain medicinal plant whose root
extracts are used in traditional Chinese medicine as a hemostatic, antitussive,
and tonic in the treatment of gynecological diseases. The aim of the study was
to obtain R. quadrifida cultures at different degrees of differentiation in vitro
and compare their growth characteristics and the content of salidroside and rosavin. Hairy roots were obtained by incubating cotyledons and hypocotyls in a suspension of Agrobacterium rhizogenes strain A4. The presence of the rolB and
rolC genes was proven by polymerase chain reaction. The obtained roots were
cultivated in Murashige-Skoog medium (MS). Calluses were obtained from the
hairy roots in MS medium with the addition of hormones: 3 mg/L 2,4 D and
0.5 mg/L BAP. The presence of the main secondary metabolites of R. quadrifida,
salidroside and rosavin, in calluses and salidroside in hairy roots by HPLC/MS
was confirmed. The content of salidroside in callus culture was significantly
higher than in hairy roots, 0.158 and 0.047%, respectively. The content of rosavin
in callus culture was 0.07%. The content of rosavin and salidroside in callus culture
was close to the level of these substances in the rhizomes of R. quadrifida plants
growing in vivo, making this culture promising for its possible biotechnological use. 相似文献
6.
Mamilov N. Sh. Konysbaev T. G. Magda I. N. Vasil’eva E. D. 《Journal of Ichthyology》2021,61(3):339-347
Journal of Ichthyology - Based on the morphological features, four rare alien species in the Kapchagai reservoir were identified: Coregonus peled, Parasalmo mykiss, Megalobrama mantschuricus, and... 相似文献
7.
N. F. Myasoedov L. A. Andreeva L. A. Lyapina T. A. Shubina M. E. Grigor’eva T. Yu. Obergan 《Biology Bulletin》2013,40(3):304-306
It has been established that fivefold intranasal administration of the peptide Leu-Pro-Gly-Pro (1 mg/kg) to rats with developing refractory hyperglycemia leads to restoration and normalization of the functions of anticoagulation and insular systems. In the blood of experimental animals, there was a decrease in the sugar level and platelet aggregation and an increase in anticoagulant and all kinds of fibrinolytic (total, enzymatic, non-enzymatic, Hageman-dependent) activity. 相似文献
8.
O. V. Shelepova V. V. Kondrat’eva T. V. Voronkova L. S. Olekhnovich 《Biology Bulletin》2013,40(3):275-280
Dynamic changes in the content of acetylsalicylic acid and the output and qualitative composition of essential oil have been studied in mint plants (Mentha spicata L. and cultivar Medichka) during their ontogenesis with allowance for changes in weather conditions. Ontogenetic changes in the level of acetylsalicylic acid in leaf tissues are found to be similar in both cv. Medichka and M. spicata. In the case of cv. Medichka, this change is connected with the dynamics of the production and the qualitative composition of essential oil; in the case of M. spicata, this connection is less expressed. The role of acetylsalicylic acid and essential oil in plant adaptation to the environment is discussed. 相似文献
9.
E. N. Olsuf’eva S. E. Solov’eva M. I. Reznikova A. M. Korolev M. N. Preobrazhenskaya 《Russian Journal of Bioorganic Chemistry》2013,39(2):121-130
The coupling reagent (benzotriazole-1-yl)oxy-tris(pyrrolidino)phosphonium hexafluorophosphate (PyBOP) is widely used for the synthesis of different peptides and their amides, particularly carboxamides of glycopeptide antibiotics of the vancomycin or teicoplanin groups. The amidation reaction of the carboxyl group of the seventh amino acid residue (AA7) in antibiotics in the presence of PyBOP is not usually accompanied by the formation of significant amounts of byproducts. However, the amidation of eremomycin (I) with bulky amines (e.g., decyl amine and adamantyl amine) in the presence of PyBOP at pH ~8.5 (Et3N or (i-Pr)2EtN) yielded N-unsubstituted carboxamide of eremomycin (Ia) as an admixture. The interaction of asparagine-containing antibiotics (eremomycin or vancomycin) with the excess of PyBOP and Et3N (pH ~8.5) in the absence of amine or ammonia led to the formation of still larger amounts of corresponding unsubstituted AA7-amides (~20%). Their structure was determined by 1H NMR and ESI MS methods and confirmed by comparing with authentic samples. It is assumed that the amide group of the asparagine residue (AA3) is the source of ammonia in the unususal amidation reaction of Asn-containing antibiotics. 相似文献
10.
Mikhail Krasavin Raivis Žalubovskis Aiga Grandāne Ilona Domračeva Petr Zhmurov 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):506-510
Abstract The hypothesis that sulfocoumarin acting as inhibitors of human carbonic anhydrase (CA, EC 4.2.1.1) cancer-associated isoforms hCA IX and – hCA XII is being able to also inhibit thioredoxin reductase was verified and confirmed. The dual targeting of two cancer cell defence mechanisms, i.e. hypoxia and oxidative stress, may both contribute to the observed antiproliferative profile of these compounds against many cancer cell lines. This unprecedented dual anticancer mechanism may lead to a new approach for designing innovative therapeutic agents. 相似文献