scholarly journals Оцінка токсикорезистентності ставковика озерного (Mollusca: Gastropoda) до впливу йонів мангану (II) у водному середовищі

2018 ◽  
Vol 8 (1) ◽  
pp. 719-729
Author(s):  
T.V. Pinkina ◽  
A.A. Pinkin

<p>Under the conditions of growing environmental pollution heavy metal ions took one of the first places among other pollutants. Nowadays annual anthropic entry of a great number of heavy metals into hydrosphere several times exceeded the entry from natural sources. The topicality of the research influence of the above pollutants on hydrobionts with the aim of introducing the research results to the ecological monitoring system is beyond doubt. <em>Lymnaea stagnalis</em> (Linné, 1758) a secondary-water lung pondmollusc, can be a suitable object for toxicological investigations. The fundamental ecotoxicological indices of <em>L</em><em>.</em><em> stagnalis</em> effected by various concentrations of Mn<sup>2+ </sup>water environment and the ranges of acute – and chronically lethal, trausferred and subthreshold toxicant concentrations as well as the decrease of toxicity of ions covered have been determined. The fundamental ecotoxicological indices of <em>L</em><em>.</em><em> stagnalis</em> effected by various concentrations of Mn<sup>2+</sup> water environment and the ranges of acute – and chronically lethaled, trausferred and subthreshold toxicant concentrations as well as the decrease of toxicity of manganese ions (ІІ) covered have been determined. The effect of Mn<sup>2+</sup> on dimensional and weight characteristics and the survival of adult and young mollusks has been studied. Reversibility of poisoning <em>L</em><em>.</em><em> stagnalis</em> by different Mn<sup>2+</sup> has been studied. Restoration of the broken functions is of a reversible nature. The linear indices varying considerably with toxicity have been distinguished. At first the aquatic balance in the bodies of mollusks is becoming positive along with the increase in the heavy metal concentrations in the environment, while under the toxicant concentration increase the balance gradually tends to be positive. The paper covers the effects of manganese ions on the pond snail behavioral reactions. The paper investigates the effects of Mn<sup>2+</sup> (acute lethal concentration – 100‒195 mg/dm<sup>3</sup>; chronically lethal – 35‒95 mg/dm<sup>3</sup>; trausferred – 0,3‒20 mg/dm<sup>3</sup>; subthreshold concentration – 1 mg/dm<sup>3</sup>) on the peculiarities of <em>L</em><em>.</em><em> stagnalis</em> reproduction and development. There have been determinate sensitive ethological responses of <em>L</em><em>. </em><em>stagnalis</em> at their reproductive period in the polluted environment. The studies have been made into structural stability of mollusk syncapsule, the peculiarities of their texture and formation physiology as well as an incidence of evolution disturbances at different intoxication levels by manganese ions (ІІ). The research makes it possible to ecologically estimate the nature of the substance influence and the response of the affected organism.</p>


Author(s):  
Aleksandr Gorbunov ◽  
Dmitry Nikiforov-Nikishin ◽  
Oleg Gorbunov

The article highlights the research of embryonic development of hydrobionts under the influence of anthropogenic factors of water solutions – chlorobenzene and tetrachloroethylene. To detect the toxicity of chloride pollutants in a freshwater reservoir, representatives of benthic mollusks (big pond snail Lymnaea stagnalis L.) were used as a model organism. According to the results of research, it was found that at a concentration of 0.01 mg/l of chlorobenzene solution individual anomalies of embryonic development of the pond fish are observed, but at higher concentrations its development is delayed by 5-6 stages in comparison with the control. As an integral parameter of pond fish development, we can take indicators of the biological toxicity criterion: Hatchling and its survival over a 10-day period after leaving the egg shells. Changes in the physiological parameters of pond fish embryos begin with a chlorobenzene concentration of 0.01 mg/l; the maximum permissible concentration for tetrachloroethylene for the considered biological indicators should be considered 0.05 mg/l. It is noted that in big pond snail (Lymnaea stagnalis L.) the hatch of juveniles from egg shells is the most sensitive indicator when determining the toxicity of an aqueous solution; and less sensitive indicators are the number of eggs laid and the survival of juveniles in the first 10 days after hatching. The test object used is a large pond, which has shown a high sensitivity to contamination of the water environment with chlorinated ecotoxicants and can be recommended for a comprehensive quality assessment when biotesting freshwater waters



2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Nicolas Cerveau ◽  
Daniel John Jackson

AbstractMicroRNAs (miRNAs) are a deeply conserved class of small, single stranded RNA molecules that post-transcriptionally regulate mRNA levels via several targeted degradation pathways. They are involved in a wide variety of biological processes and have been used to infer the deep evolutionary relationships of major groups such as the Metazoa. Here we have surveyed several adult tissues of the freshwater pulmonate Lymnaea stagnalis (the Great Pond Snail) for miRNAs. In addition we perform a shell regeneration assay to identify miRNAs that may be involved in regulating mRNAs directly involved in the shell-forming process. From seven mature tissues we identify a total of 370 unique precursor miRNAs that give rise to 336 unique mature miRNAs. While the majority of these appear to be evolutionarily novel, most of the 70 most highly expressed (which account for 99.8% of all reads) share sequence similarity with a miRBase or mirGeneDB2.0 entry. We also identify 10 miRNAs that are differentially regulated in mantle tissue that is actively regenerating shell material, 5 of which appear to be evolutionarily novel and none of which share similarity with any miRNA previously reported to regulate biomineralization in molluscs. One significantly down-regulated miRNA is predicted to target Lst-Dermatopontin, a previously characterized shell matrix protein from another freshwater gastropod. This survey provides a foundation for future studies that would seek to characterize the functional role of these molecules in biomineralization or other processes of interest.



1998 ◽  
Vol 32 (1) ◽  
pp. 57-63 ◽  
Author(s):  
Hisayo Sadamoto ◽  
Dai Hatakeyama ◽  
Satoshi Kojima ◽  
Yutaka Fujito ◽  
Etsuro Ito


2021 ◽  
Vol 25 (5) ◽  
pp. 52-57
Author(s):  
S.I. Alekseeva ◽  
Zh.M. Okhlopkova

The methods of biotesting of the aquatic environment based on the representative of the duckweed family (lat. Lemnaceae) greater duckweed (Spirodela polyrhiza (L.) Schleid) were considered. A review is presented on the use of greater duckweed as a model object in biological testing, in partic-ular, when exposed to heavy metals salts. When cultivated Spirodela polyrhiza with the addition of heavy metals salts, a change in the growth and development of plants in the experienced line of plants was revealed, as well as a decrease in the content of chlorophyll a and b.





2011 ◽  
Vol 214 (15) ◽  
pp. 2528-2533 ◽  
Author(s):  
S. Dalesman ◽  
V. Karnik ◽  
K. Lukowiak
Keyword(s):  


Sign in / Sign up

Export Citation Format

Share Document