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Start Over Coverage 495-504

2. High prevalence of trypanosome co-infections in freshwater fishes

Creator:
Grybchuk-Ieremenko, Anastasiia, Losev, Alexander, Kostygov, Alexei Yu., Lukeš, Julius, and Yurchenko, Vyacheslav
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Trypanosoma, blood parasites, mixed infections, phylogeny, 18S rRNA, and teleosts
Language:
English
Description:
One thousand three hundred seventy three fish specimens of eight different species from the vicinity of Kyiv, Ukraine, were examined for the presence of trypanosomes and 921 individuals were found to be infected. The prevalence of infection ranged from 24% in freshwater bream, Abramis brama (Linnaeus), to 100 % in spined loach, Cobitis ''taenia'' Linnaeus. The level of parasitaemia also varied significantly between generally mild infections in pikeperch, Sander lucioperca (Linnaeus), and heavy ones in C. ''taenia''. In most cases the infections with trypanosomes were asymptomatic. Cases of co-infection with species of Trypanoplasma Laveran et Mesnil, 1901 were documented for five out of eight examined host species. Molecular analysis of the 18S rDNA sequences revealed that four hosts, namely northern pike, Esox lucius Linnaeus, freshwater bream, spined loach and European perch, Perca fluviatilis Linnaeus, were simultaneously infected with two different trypanosome species. Our findings advocate the view that to avoid the risk posed by mixed infections, subsequent molecular taxonomic studies should be performed on clonal lines derived from laboratory cultures of fish trypanosomes.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Tolerance mechanisms in Cassia alata exposed to cadmium toxicity - potential use for phytoremediation

Creator:
Silva, J. R. R., Fernandes, A. R., Silva Junior, M. L., Santos, C. R. C., and Lobato, A. K. S.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
těžké kovy, heavy metals, kadmium, fytoremediace, cadmium, phytoremediation, detoxifikace, výměna plynu, reaktivní formy kyslíku, remediace, detoxification, gas exchange, reactive oxygen species, remediation, Cassia alata, 2, and 581
Language:
Multiple languages
Description:
Cadmium is often detected in areas contaminated by heavy metals and the incidence of this element in dangerous concentrations has been increasing due to anthropogenic activities. The aim of this research was to determine Cd concentrations in tissues, quantify compounds, pigments and enzymes, and to evaluate the gas exchange. Our aim was also to identify components that can modify and contribute to tolerance of Cassia alata against Cd toxicity. We used five Cd concentrations (0, 22, 44, 88, and 132 μM) to validate our hypothesis. The Cd concentrations in tissues of C. alata plants increased significantly, compared with the control treatment, in the following graduated sequence: root > leaf > stem. Progressive enhancement in glutathione (GSH) was verified in plants treated with all Cd concentrations used, when compared with treatment without Cd. Antioxidant enzyme activities presented similar patterns with progressive enhancements, being a desirable characteristic for plants with a potential to hyperaccumulate Cd. Our results suggest that C. alata plants can be used for phytoremediation programs. Their defense mechanism is based on Cd accumulation in roots, coupled with increase in GSH and the efficient activity of antioxidant enzymes that contribute to minimize the oxidative stress and consequently improve the protection of the metabolic machinery., J. R. R. Silva, A. R. Fernandes, M. L. Silva Junior, C. R. C. Santos, A. K. S. Lobato., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public