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Desiccation in general leads to severe damage of cellular structures, which commonly results in the death of cells and the organism. However, a number of so-called anhydrobiotic organisms have developed remarkable mechanisms, allowing them to minimize or avoid such damage and survive extreme dehydration in a cryptobiotic state [1][2][3][4][5][6]. Several species of invertebrate taxa have this ability, including the embryonic cysts of crustaceans, rotifers, insect larvae, nematodes and tardigrades [2,3,[7][8][9][10][11][12]. Additionally, many procaryotes, such as bacteria and cyanobacteria [13,14], and even plant seeds [15][16][17][18][19] and adult plants, for example the resurrection lycopode Selaginella lepidophylla [5,20], demonstrate dehydration tolerance. Although Antonin van Leuwenhoek described anhydrobiosis over 300 years ago [21], the underlying mechanisms are still not fully understood. However, over the last three decades, researchers have come to recognize the important role of polyhydroxy compounds such as the non-reducing disaccharide trehalose [22][23][24]. This sugar is found in high concentrations in a wide variety of anhydrobiotic organisms, including nematodes, embryonic cysts of crustaceans, and yeast. Trehalose concentrations as high as 13-18% of the dry weights have been reported for anhydrobiotic cysts of the crustacean Artemia franciscana [25][26][27] whereas the nematode Aphelenchus avenae can accumulate 10-15% of its dry weight as trehalose during anhydrobiosis [8,9]. Studies on the anhydrobiotic insect larvae Polypedilum vanderplanki report up to 18% trehalose in the dry body mass [11]. Significantly increased trehalose levels also have been found in the Arctic collembolan Onychiurus arcticus during partial desiccation, induced by sub-zero temperatures [28]. The disaccharide sucrose fulfils a similar role in plants and accumulates in desiccation-tolerant plant seeds and resurrection To withstand desiccation, many invertebrates such as rotifers, nematodes and tardigrades enter a state known as anhydrobiosis, which is thought to require accumulation of compatible osmolytes, such as the non-reducing disaccharide trehalose to protect against dehydration damage. The trehalose levels of eight tardigrade species comprising Heterotardigrada and Eutardigrada were observed in five different states of hydration and dehydration. Although many species accumulate trehalose during dehydration, the data revealed significant differences between the species. Although trehalose accumulation was found in species of the order Parachela (Eutardigrada), it was not possible to detect any trehalose in the species Milnesium tardigradum and no change in the trehalose level has been observed in any species of Heterotardigrada so far investigated. These results expand our current understanding of anhydrobiosis in tardigrades and, for the first time, demonstrate the accumulation of trehalose in developing tardigrade embryos, which have been shown to have a high level of desiccation tolerance.Abbreviations HPAEC, h...

Cisplatin preferentially accumulates in cells of the S3 segment of the renal proximal tubule and is toxified intracellularly by hydration. The earliest manifestation of toxicity is inhibition of protein synthesis. GSH depletion is another important mechanism causing CP toxicity. Intracellular binding to SH groups leads to GSH depletion, resulting in lipid peroxidation and eventually mitochondrial damage. New measures to prevent GSH depletion and scavenge intracellular free oxygen radicals have been tried in clinical studies. Promising results indicate that cisplatin nephrotoxicity can be further reduced in the future.

The current paper critically reviews the state-of-the-science on (1) microplastics (MP) types and particle concentrations in freshwater ecosystems, (2) MP and nanoplastics (NP) uptake and tissue translocation, (3) MP/NP-induced effects in freshwater organisms, and (4) capabilities of MP/NP to modulate the toxicity of environmental chemicals. The reviewed literature as well as new data on MP and NP concentrations in the river Elbe and on particle uptake into human cells indicate an environmental relevance of small particles in the low nano-and micrometer range higher than that of larger MP.

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