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Earthworms belonging to oligochaete annelids became a model for comparative immunologists in the early sixties with the publication of results from transplantation experiments that proved the existence of self/nonself recognition in earthworms. This initiated extensive studies on the earthworm immune mechanisms that evolved to prevent the invasion of pathogens. In the last four decades important cellular and humoral pathways were described and numerous biologically active compounds were characterized and often cloned.
- MeSH
- buněčná imunita imunologie MeSH
- humorální imunita imunologie MeSH
- Oligochaeta genetika imunologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
Eisenia lucens is an earthworm living in the organic soil layer of decomposing wood. When irritated, the worm expels coelomic fluid through pores in its body wall, exhibiting blue-green bioluminescence. The mechanism of the bioluminescence, which seems to be different from other bioluminescence systems of terrestrial animals, has been studied in this work. Many lines of evidence indicate that riboflavin stored in coelomycetes plays an important role in this glowing reaction.
- MeSH
- fluorescenční mikroskopie MeSH
- luminiscence MeSH
- Oligochaeta cytologie fyziologie MeSH
- riboflavin metabolismus MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Sludge treatment wetlands (STWs) have been used for sludge treatment in recent years, however, heavy metals (HMs) are one of the limiting factors for the final sludge application, and the fate of HMs in STWs are still not well studied. Therefore, six STWs with two plant species and earthworm addition were investigated to evaluate their effects on HMs distribution and bioavailability. The results showed that plant uptake of HMs was insignificant with earthworm addition. Earthworm had the highest enrichment for Cd with bioaccumulation factors of 6.9-7.3. Moreover, earthworm had a positive effect to remove HMs in accumulated sludge. Meanwhile, the bioavailability of Cd in accumulated sludge was decreased by earthworm addition, with the acid-soluble fraction decreased from range 16.5-22.7% to range 7.2-10.1%. Furthermore, HMs mass balance in the STWs revealed that HMs were widely distributed in the accumulated sludge, leachate and others, while their (except Cd) accumulation in the plants and earthworm are less than 1%. The Cd toxicity in the accumulated sludge can be reduced by the addition of earthworm with enrichment of 3.6-8.2%. Overall, earthworm addition have positive effects on distribution and bioavailability of HMs in STWs.
- MeSH
- biologická dostupnost MeSH
- mokřady * MeSH
- odpadní vody * MeSH
- Oligochaeta metabolismus MeSH
- těžké kovy farmakokinetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Earthworm density and feeding during exposure to contaminated soil have been used inconsistently in bioaccumulation studies, which may lead to possible errors in risk assessment and modeling. Hydrophobic organic pollutants with a wide range of environmental properties (phenanthrene, pyrene, lindane, p,p'-DDT, and PCB 153) were used to study the effect of different earthworm densities in combination with the presence or absence of feeding on bioaccumulation factors (BAFs). Similar BAFs were found at various soil-to-worm ratios, with the exception of phenanthrene. We recommend using at least 15 gsoil dw per earthworm. The absence of feeding doubled the BAFs and, thus, using no food ration can be considered as "the worst case scenario". Whenever food is to be applied (i.e. to ensure the validity of the test in earthworm mass loss), we suggest feeding depending on the organic carbon content of the studied soil.
- MeSH
- DDT farmakokinetika MeSH
- fenantreny farmakokinetika MeSH
- hexachlorcyklohexan farmakokinetika MeSH
- hustota populace MeSH
- látky znečišťující půdu farmakokinetika MeSH
- Oligochaeta metabolismus fyziologie MeSH
- polychlorované bifenyly farmakokinetika MeSH
- půda chemie MeSH
- pyreny farmakokinetika MeSH
- stravovací zvyklosti MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The massive production and use of silver nanoparticles (Ag NPs) have led to their increasing release into the environment. Even though the antimicrobial and cytotoxic effects of native nanoparticles have been well studied, the environmental impacts of transformation products such as silver sulfide nanoparticles (Ag2S NPs) have not been elucidated. In the present study, we assessed the toxicity of Ag2S NPs and silver nitrate (AgNO3), as a source of Ag, to the earthworm Eisenia andrei using a nominal concentration of 5 mg Ag kg-1 soil. We used the OECD guidelines to assess effects on weight loss and mortality for 14 days. After exposure, we also extracted the immune effector cells (coelomocytes) and conducted a battery of biomarker tests. To ensure the quality of the toxicological results, the structural changes of NPs during the experiment and the uptake of silver by the earthworms were monitored. During the experiment, mortality effects were not detected, but a weight loss was observed in the earthworms exposed to Ag2S NPs. Altough Ag2S NPs were engulfed by E. andrei cells, neither phenoloxidase activity nor lipid peroxidation differed from the untreated control group. Cells from earthworms treated with Ag2S NPs exerted very broad value range of nitric oxide (NO) generation, suggesting an imbalance in the NO metabolism. Overall, this study suggests minimal risks associated with Ag2S NPs exposure to earthworms. However, further studies are needed to assure no immunotoxicological or chronic effects on a wider range of terrestrial organisms.
- MeSH
- dusičnan stříbrný toxicita MeSH
- hmotnostní úbytek MeSH
- kovové nanočástice * chemie toxicita MeSH
- látky znečišťující půdu * toxicita MeSH
- Oligochaeta * MeSH
- půda chemie MeSH
- sloučeniny stříbra MeSH
- stříbro metabolismus toxicita MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Vermicomposting is a process by which earthworms together with microorganisms degrade organic wastes into a humus-like material called vermicompost. This process does not include a thermophilic stage, and therefore, the possible presence of pathogens represents a potential health hazard. To elucidate the effect of earthworms in the selective reduction of pathogens, grape marc substrate was artificially inoculated with Escherichia coli, Enterococcus spp., thermotolerant coliform bacteria (TCB), and Salmonella spp., and their reduction during vermicomposting was monitored. Various defense mechanisms eliminating microorganisms in the earthworm gut were assumed to be involved in the process of pathogen reduction. Therefore, we followed the expression of three pattern recognition receptors (coelomic cytolytic factor (CCF), lipopolysaccharide-binding protein (LBP), and Toll-like receptor (v-TLR)), two antimicrobial molecules (fetidin/lysenins and lysozyme), and heat shock protein HSP70. We detected the significant decrease of some defense molecules (fetidin/lysenins and LBP) in all pathogen-inoculated substrates, and the increase of CCF and LBP in the Salmonella spp.-inoculated substrate. At the same time, the reduction of pathogens during vermicomposting was assessed. We observed the accelerated reduction of E. coli, Enterococcus spp., and TCB in pathogen-inoculated substrates with earthworms compared to that without earthworms. Moreover, the differences between the microbiome of grape marc substrate and earthworm intestines were determined by high throughput sequencing. This analysis revealed that the bacterial composition of grape marc substrate differed from the composition of the content of earthworm intestines, suggesting the elimination of specific bacterial species during food passage through the gut.
- MeSH
- Bacteria MeSH
- Escherichia coli MeSH
- mikrobiota * MeSH
- Oligochaeta * MeSH
- půda MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Sewage sludge treatment is becoming one of the most significant challenges for domestic wastewater management. Optimization of sludge management for reducing sludge handling cost in wastewater treatment plant is highly demanded. Sludge treatment reed bed system (STRB) is an eco-environmentally friendly technology which has a low investment input and reduced costs for operation and maintenance. The objective of this study is to evaluate the effect of earthworm assistant STRB in terms of sludge dewatering and stabilization of surplus sludge. The results show that draining and evapotranspiration (ET) take the main role for sludge dewatering; with maximum of 77 and 43 % water was removed through draining and ET, respectively. Plants improved ET rate up to 13.1 % in the planted STRB compare with the unplanted STRB. The combination of plants and earthworms increased ET rate of 20.9 % more than the control STRB (unplanted without earthworms). The planted STRB with earthworm reached the lowest water content in accumulated sludge of 46 %. There was a systematic increase of total solids (TS) concentration from 0.5 % in the influent to 25-54 % in the accumulated sludge. Earthworms enhanced the sludge stabilization dramatic with the ratio of volatile solids (VS)/TS decreased from 49 % in the influent to 18 % in the accumulated sludge in the earthworm assistant STRB. The results demonstrated a good efficiency for sludge dewatering and stabilization with the assistant of earthworms in STRBs, which can be an alternative technology for sludge treatment in wastewater treatment plants.
- MeSH
- kvalita vody MeSH
- mokřady * MeSH
- nakládání s odpady metody MeSH
- odpadní vody * MeSH
- Oligochaeta fyziologie MeSH
- voda MeSH
- zázvorníkotvaré * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
The miniature excitatory postsynaptic currents (MEPCs) of the muscle cells of the earthworm Lumbricus terrestris were recorded by glass microelectrodes. In a single synaptic zone, three types of MEPC were recorded: a fast singleexponential type that decayed with ? =0.9 ms, a slow single-exponential with ? = 9.2 ms and a two-exponential MEPC with ? = 1.3 and 8.5 ms, respectively. The muscle cells of earthworms contain populations of yet-unidentified ionic channels that might be different from the common nicotinic and muscarinic groups of acetylcholine receptors, since these MEPCs are not sensitive to d-tubocurarine, atropine, benzohexonium or proserine. Alternatively, besides ACh receptors, the membrane may contain receptors for another yet-unidentified excitatory transmitter.
