<i>Paramacrobiotus lachowskae</i>, a new species of Tardigrada from Colombia (Eutardigrada: Parachela: Macrobiotidae)

<p>In this article we describe a new <i>Paramacrobiotus</i> species of the <i>areolatus</i> group by means of integrative taxonomy. Together with the detailed morphological and morphometric data (obtained from light and scanning electron microscopy) we also provide DNA sequences of four universal molecular markers used in tardigrade taxonomy (three nDNA fragments: 18S rRNA, 28S rRNA, ITS-2, and one mtDNA fragment: COI). The animals of <i>Paramacrobiotus lachowskae</i> sp. nov. are similar to several species of the <i>areolatus</i> complex and the eggshell ornamentation is similar to that of two species of the <i>richtersi</i> group. Therefore, the new species can be easily distinguished from the <i>areolatus</i> group species by egg morphology (dome-like, wrinkled processes with long flexible spines/filaments covered by fine short hairs) and from species of the <i>richtersi</i> complex by the absence of the microplacoid. <i>Paramacrobiotus lachowskae</i> sp. nov. is the 43rd species reported from Colombia and fifth <i>Paramacrobiotus</i> species from this South American country.</p> <p><a href="http://zoobank.org/urn:lsid:zoobank.org:pub:FEDC11D3-DCCF-4699-A704-CE6DEA1CDED4" target="_blank">http://zoobank.org/urn:lsid:zoobank.org:pub:FEDC11D3-DCCF-4699-A704-CE6DEA1CDED4</a></p

An integrative revision of <i>Mesocrista</i> Pilato, 1987 (Tardigrada: Eutardigrada: Hypsibiidae)

<p><i>Mesocrista</i> is a Holarctic tardigrade genus currently classified within the subfamily Itaquasconinae (Eutardigrada: Parachela: Hypsibiidae). The position of the genus has been so far inferred solely on the basis of light microscopy observations. Here, we present the first-ever scanning electron microscopy images of a dissected bucco-pharyngeal apparatus and DNA sequences for <i>Mesocrista</i> from Spitsbergen, mainland Norway and Poland. The new data allowed an integrative redescription of the nominal <i>M. spitzbergensis</i> from the <i>locus typicus</i> and uncovered a new species, <i>M. revelata</i>, from the European localities. The two species differ phenotypically by the oral cavity armature and claw morphology as well as by a number of morphometric traits, and they are also distinct genetically in all sequenced DNA markers, three nuclear (18S rRNA, 28S rRNA, ITS-2) and one mitochondrial (COI). Both molecular and morphometric data presented in this paper suggest that previous records of <i>M. spitzbergensis</i> should be treated with caution, since most probably some of them signify different <i>Mesocrista</i> species. Our phylogenetic analysis confirmed that <i>Mesocrista</i> is indeed a member of the Itaquasconinae. We also found that the most closely related, among genera for which there are molecular data available, is <i>Adropion</i>, from which <i>Mesocrista</i> differs by the shape of the apophyses for insertion of stylet muscles and the width of the bucco-pharyngeal tube. Finally, we advocate that <i>Diphascon marcusi</i>, a rare species hypothesised to represent either <i>Mesocrista</i> or <i>Adropion</i>, should be transferred to the latter genus and that the species should be redescribed to confirm its validity and systematic position.</p> <p><a href="http://zoobank.org/urn:lsid:zoobank.org:pub:6515D58D-8469-4854-8687-177232112BDA" target="_blank">http://zoobank.org/urn:lsid:zoobank.org:pub:6515D58D-8469-4854-8687-177232112BDA</a></p

Results of <i>Experiment II</i>.

<p>Mortality of <i>H</i>. <i>dujardini</i> during entering into cryptobiosis in isolating chamber (test group) and under influence of geomagnetic field (control group).</p

Results of Experiment I.

<p>Mortality of anhydrobiotic specimens of <i>H</i>. <i>dujardini</i> (ID- number of Petri dish, LS-live specimens, DS-dead specimens, M-mortality).</p

Can the tardigrade <i>Hypsibius dujardini</i> survive in the absence of the geomagnetic field?

<div><p>Earth's geomagnetic field has undergone critical changes in the past. Studies on the influence of the magnetic field on Earth’s organisms are crucial for the understanding of evolution of life on Earth and astrobiological considerations. Numerous studies conducted both on plants and animals confirmed the significant influence of the geomagnetic field on the metabolism of living organisms. Water bears (Tardigrada), which are a mong the most resistant animals due to their cryptobiotic abilities, show significant resistance to a number of environmental stressors, but the influence of the geomagnetic field on their fitness has not been addressed before. In our studies, we used eutardigrade <i>Hypsibius dujardini</i> to analyse whether isolation from the geomagnetic field had an effect on mortality. We found that <i>Hypsibius dujardini</i> specimens demonstrated relatively high mortality during anhydrobiosis, also in control groups exposed to the normal geomagnetic field. Moreover, similar mortality was observed in anhydrobiotic specimens isolated from the geomagnetic field. However, a significant difference was noted between tardigrade survival and the moment of their isolation from the geomagnetic field. In particular, tardigrade mortality substantially increased in absence of a magnetic field during the process of entering anhydrobiosis and returning to active life. Our results suggest that these processes rely on complex metabolic processes that are critically influenced by the geomagnetic field.</p></div

Comparisons of mortalities of <i>H</i>. <i>dujardini</i> specimens between experiments I, II and III.

<p>Comparisons of mortalities of <i>H</i>. <i>dujardini</i> specimens between experiments I, II and III.</p

Comparison of the mortality of <i>H</i>. <i>dujardini</i> returning to active live: In isolating chamber (test group) and under influence of geomagnetic field (control group).

<p>Comparison of the mortality of <i>H</i>. <i>dujardini</i> returning to active live: In isolating chamber (test group) and under influence of geomagnetic field (control group).</p

Anti-magnetic chamber (CIMF—Chamber isolated from magnetic field).

<p>A—chamber during work, connected with laptop, B—schematic graph of the chamber (1–1 mm thickness mu-metal composed of nickel and iron, 2—inside of the chamber, 3—plastic base), C–inside of the chamber, shelves with tardigrade cultures in Petri dishes.</p

Synthesis and Biological Evaluation of New Amino Acid and Dipeptide Derivatives of Neocryptolepine as Anticancer Agents

The syntheses of neocryptolepine derivatives containing an amino acid or a dipeptide at the C-9 position and their evaluation for antitumor activity in vitro and in vivo are reported. To establish the influence of an amino acid or a peptide on the physicochemical properties of 5<i>H</i>-indolo­[2,3-<i>b</i>]­quinoline (DiMIQ), lipophilic and hemolytic properties were investigated. Most of the compounds displayed a high antiproliferative activity in vitro and strongly inhibited growth of tumor in mice compared to cyclophosphamide. The attachment of the hydrophilic amino acid or the peptide to the hydrophobic DiMIQ increased its hydrophilic properties and decreased its hemolytic activity. The glycylglycine conjugate (<b>7a</b>) was the most promising derivative. It strongly inhibited the growth of the tumor in mice (at dose 50 mg kg^–1 day^–1 it inhibited the tumor growth by 46–63% on days 11–16 and by 29–43% on days 18–23) and significantly decreased hemolytic activity and lowered the in vivo toxicity compared to DiMIQ