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1.
A survey of toxicity of cyanobacterial blooms in Lake Ladoga and adjacent water bodies 总被引:3,自引:1,他引:2
Boris V. Gromov Alexey A. Vepritsky Kira A. Mamkaeva Lyudmila N. Voloshko 《Hydrobiologia》1996,322(1-3):149-151
Twentyfive cyanobacterial blooms in Lake Ladoga and adjacent water bodies were studied in the summer of 1990–1992. Toxicity of the water bloom material for mice was detected in 9 cases. The maximal tolerable doses (MTD) of the material extracted from biomass varied within 3–30 mg kg–1 mouse body weight; 50% lethal doses (LD50) were within 45–125 mg kg–1. Toxic water blooms were registered in Karelian lakes and in the Neva Bay, Gulf of Finland. Cyanobacterial samples collected on the eastern coast of Lake Ladoga proved to be non-toxic. The species identified in toxic bloom material included Anabaena circinalis, A. flos-aquae, A. lemmermannii, Anabaena sp., Aphanizomenonflos-aquae, Gloeotrichia echinulata, G. pisum, Microcystis aeruginosa and Oscillatoria sp. These data suggest that toxic forms of cyanobacteria are widespread in Karelian lakes belonging to the drainage basin of Lake Ladoga. 相似文献
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Ilja I. Brusentsov Alexey V. Katokhin Irina V. Brusentsova Sergei V. Shekhovtsov Sergei N. Borovikov Grigoriy G. Goncharenko Lyudmila A. Lider Boris V. Romashov Olga T. Rusinek Samat K. Shibitov Marat M. Suleymanov Andrey V. Yevtushenko Viatcheslav A. Mordvinov 《PloS one》2013,8(4)
Opisthorchis felineus or Siberian liver fluke is a trematode parasite (Opisthorchiidae) that infects the hepato-biliary system of humans and other mammals. Despite its public health significance, this wide-spread Eurasian species is one of the most poorly studied human liver flukes and nothing is known about its population genetic structure and demographic history. In this paper, we attempt to fill this gap for the first time and to explore the genetic diversity in O. felineus populations from Eastern Europe (Ukraine, European part of Russia), Northern Asia (Siberia) and Central Asia (Northern Kazakhstan). Analysis of marker DNA fragments from O. felineus mitochondrial cytochrome c oxidase subunit 1 and 3 (cox1, cox3) and nuclear rDNA internal transcribed spacer 1 (ITS1) sequences revealed that genetic diversity is very low across the large geographic range of this species. Microevolutionary processes in populations of trematodes may well be influenced by their peculiar biology. Nevertheless, we suggest that lack of population genetics structure observed in O. felineus can be primarily explained by the Pleistocene glacial events and subsequent sudden population growth from a very limited group of founders. Rapid range expansion of O. felineus through Asian and European territories after severe bottleneck points to a high dispersal potential of this trematode species. 相似文献
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Lyudmila E. Minchenkova Anna K. Schyolkina Boris K. Chernov Valery I. Ivanov 《Journal of biomolecular structure & dynamics》2013,31(3):463-476
Abstract Self-complementary decadeoxynucleotides, CCGATATCGG, CCAGATCTGG, CCCTG- CAGGG, GGGGGCCCCC, were designed and synthesized to estimate the A-philic free energy of CC/GG contacts. First, regions of temperature-stability of the double-stranded conformation were determined for each 10-mer. Then, circular dichroism spectra were recorded for the B-family forms at different temperatures, counter-ion concentrations and trifluoroethanol contents. A cooperative change typical of the B-A transition is observed in the CD spectra at a trifluoroethanol content specific for each duplex. The positions of half-transition points were functions not only of the nucleotide sequence but of the duplex length as well: the B to A transitions were hindered in these 10-mers in comparison with a lengthy DNA. The B-phility value was estimated to be 3 kcal/mol of 10-mer. The B-A transition point was shown to drop with an increase in the number of CC/GG contacts in a duplex. The designed 10-mers made it possible to estimate quantitatively the A- phility of CC/GG contact as compared with an average DNA: (FA-FB)CC=0.2 Kcal/mol, (FA-FB)DNA=0.7 Kcal/mol. 相似文献
6.
Protein changes and proteolytic degradation in red and white clover plants subjected to waterlogging
Veselin Stoychev Lyudmila Simova-Stoilova Irina Vaseva Anelia Kostadinova Rosa Nenkova Urs Feller K. Demirevska 《Acta Physiologiae Plantarum》2013,35(6):1925-1932
Red (Trifolium pratense L., cv. “Start”) and white clover varieties (Trifolium repens L., cv. “Debut” and cv. “Haifa”) were waterlogged for 14 days and subsequently recovered for the period of 21 days. Physiological and biochemical responses of the clover varieties were distinctive, which suggested different sensitivity toward flooding. The comparative study of morphological and biochemical parameters such as stem length, leaflet area, dry weight, protein content, protein pattern and proteolytic degradation revealed prominent changes under waterlogging conditions. Protease activity in the stressed plants increased significantly, especially in red clover cv. “Start”, which exhibited eightfold higher azocaseinolytic activity compared to the control. Changes in the protein profiles were detected by SDS-PAGE electrophoresis. The specific response of some proteins (Rubisco, Rubisco-binding protein, Rubisco activase, ClpA and ClpP protease subunits) toward the applied stress was assessed by immunoblotting. The results characterized the red clover cultivar “Start” as the most sensitive toward waterlogging, expressing reduced levels of Rubisco large and small subunits, high content of ClpP protease subunits and increased activity of protease isoforms. 相似文献
7.
Ilya A. Volodin Olga V. Sibiryakova Lyudmila E. Kokshunova Roland Frey Elena V. Volodina 《Bioacoustics.》2013,22(2):79-98
The trunk-like nose of the saiga antelope Saiga tatarica is a striking example of an exaggerated trait, assumed to having evolved as a dust filter for inhaled air. In addition, it functions to elongate the vocal tract in harem saiga males for producing low-formant calls that serve as a cue to body size for conspecifics. This study applies the source–filter theory to the acoustics of nasal, oral and nasal-and-oral calls that were recorded from a captive herd of 24 mother and 32 neonate saigas within the first 10 days postpartum. Anatomical measurements of the nasal and oral vocal tracts of two specimens (one per age class) helped to establish the settings for the analysis of formants. In both mother and young, the lower formants of nasal calls/call parts were in agreement with the source–filter theory, which suggests lower formants for the longer nasal vocal tract than for the shorter oral vocal tract. Similar fundamental frequencies of the nasal and oral parts of nasal-and-oral calls were also in agreement with the source–filter theory, which postulates the independence of source and filter. However, the fundamental frequency was higher in oral than in nasal calls, probably due to the higher emotional arousal during the production of oral calls. We discuss production mechanisms and the ontogeny of formant patterns of oral and nasal calls among bovid and cervid species with and without a trunk-like nose. 相似文献
8.
Lyudmila A. Romanenko Naoto Tanaka Natalia I. Kalinovskaya Valery V. Mikhailov 《World journal of microbiology & biotechnology》2013,29(7):1169-1177
The aim of this study was to survey microorganisms from the deep surface sediment samples collected from the Sea of Japan and to screen them for antimicrobial and antagonistic effects. Phylogenetic analysis revealed most isolates sharing 98–100 % sequence similarity to recognized species, including those recovered previously from marine or saline environments. Alteromonas, Halomonas, Marinobacter, Pseudoalteromonas, Salinicola, within the class Gammaproteobacteria, Sulfitobacter (Alphaproteobacteria), Bacillus, Paenibacillus and Paenisporosarcina (Firmicutes), Nocardiopsis and Streptomyces (Actinobacteria) occurred abundantly in all sediment samples. Antimicrobial screening revealed twenty three strains (13 %) capable to inhibit growth of one to eight test cultures and deep sediment isolates. Based on phylogenetic analysis mostly active strains belonged to the genera Bacillus, Brevibacillus, Nocardiopsis, Paenibacillus and Streptomyces. Antimicrobial substances (1–3) were isolated from strain Paenibacillus sp. Sl 79w showing a high inhibitory activity. On the basis of combined spectral analyses (IR, UV, 1H and 13C NMR) the compounds 1, 2 and 3 with [M + H]+ at 409.1 and 409.2 m/z, and with [M + Na]+ at 822.5 m/z were found to have a carbon skeleton of isocoumarin and peptide antibiotics, respectively. Our findings demonstrated that the deep surface sediments of the Sea of Japan represent an untapped source of diverse microorganisms capable of antimicrobial metabolite production. 相似文献
9.
Biliana Nikolova Severina Semkova Iana Tsoneva Georgi Antov Juliana Ivanova Ivanina Vasileva Proletina Kardaleva Ivanka Stoineva Nelly Christova Lilyana Nacheva Lyudmila Kabaivanova 《Engineering in Life Science》2019,19(12):978-985
Taking into account the rising trend of the incidence of cancers of various organs, effective therapies are urgently needed to control human malignancies. However, almost all chemotherapy drugs currently on the market cause serious side effects. Fortunately, several studies have shown that some non‐toxic biological macromolecules, including algal polysaccharides, possess anti‐cancer activities or can increase the efficacy of conventional chemotherapy drugs. Polysaccharides are characteristic secondary metabolites of many algae. The efficacy of polysaccharides on the normal and cancer cells is not well investigated, but our investigations proved a cell specific effect of a newly isolated extracellular polysaccharide from the red microalga Porphyridium sordidum. The investigated substance was composed of xylose:glucose and galactose:manose:rhamnose in a molar ratio of 1:0.52:0.44:0.31. Reversible electroporation has been exploited to increase the transport through the plasma membrane into the tested breast cancer tumor cells MCF‐7 and MDA‐MB231. Application of 75 µg/mL polysaccharide in combination with 200 V/cm electroporation induced 40% decrease in viability of MDA‐MB231 cells and changes in cell morphology while control cells (MCF10A) remained with normal morphology and kept vitality. 相似文献
10.
Ekaterina Spiridonova Irina Nesterkina Veronika Gurina Vadim Nurminsky Lyudmila Donskaya 《International journal of phytoremediation》2019,21(10):980-984
AbstractThe article dwells upon identifying the effect of cadmium on the roots of beetroot. The exposure effects of various concentrations of cadmium were studied at different levels of the plant organization (tissue pieces, organelles, membrane vesicles). The effect was noted only at a concentration of 100?μm. The negative effect of cadmium on the roots tissues of beetroot appeared with an increase in permeability and a decrease in the stability of cell membranes due to a change in the composition of fatty acids of membrane lipids and an increase in oxidation processes. The effect of cadmium in model experiments on the activity of the proton pumps of the vacuolar membrane has been evaluated. The pumps provide for the transport of heavy metals into the vacuole, which is one of the effective mechanisms for phytoremediation. The influence of cadmium in model experiments on the activity of the proton pump of a vacuolar membrane was evaluated. Under the influence of cadmium, a decrease in the activity of V-ATPase was observed, while the activity of V-PPase did not change. The results obtained complement our understanding of the damaging effects that occur in plant cells under cadmium stress. 相似文献