Molecular phylogeny of the other tissue coccidia: Lankesterella and Caryospora

Nearly complete sequences were obtained from the 18S rDNA genes of Eimeria falciformis (the type species of the genus), Caryospora bigenetica, and Lankesterella minima. Two clones of the rDNA gene from C. higenetica varied slightly in primary structure. Parsimony-based and maximum likelihood phylogenetic reconstructions with a number of other apicomplexan taxa support 2 major clades within the Eucoccidiorida, i.e., the isosporoid coccidia (consisting of Toxoplasma, Neospora, Isospora [in part], and Sarcocystis spp.) and a second clade containing Lankesterella and Caryospora spp., as well as the eimeriid coccidia (Cyclospora, Isospora [in part], and Eimeria spp.). Our observations suggest that Caryospora spp. may not belong in the family Eimeriidae but rather may be allied with the family Lankesterellidae with which they share molecular and life history similarities. This may be a third lineage of coccidian parasites that has independently evolved a unique heteroxenous transmission strategy.     

Environmental Controls on River Assemblages at the Regional Scale: An Application of the Elements of Metacommunity Structure Framework

Understanding factors that structure regional biodiversity is important for linking ecological and biogeographic processes. Our objective was to explore regional patterns in riverine benthic invertebrate assemblages in relation to their broad positioning along the river network and examine differences in composition, biodiversity (alpha and beta diversity), and environmental drivers. We up-scaled methods used to examine patterns in metacommunity structure (Elements of Metacommunity Structure framework) to examine faunal distribution patterns at the regional extent for 168 low-mountain stream invertebrate assemblages in central Germany. We then identified the most influential environmental factors using boosted regression trees. Faunal composition patterns were compartmentalised (Clementsian or quasi-Clementsian), with little difference from headwaters to large rivers, potentially reflecting the regional scale of the study, by crossing major catchment boundaries and incorporating different species pools. While idealised structures did not vary, environmental drivers of composition varied considerably between river sections and with alpha diversity. Prediction was substantially weaker, and the importance of space was greater, in large rivers compared to other sections suggesting a weakening in species sorting downstream. Further, there was a stronger transition in composition than for alpha diversity downstream. The stronger links with regional faunal composition than with richness further emphasises the importance of considering the alternative ways in which anthropogenic stressors are operating to affect biodiversity patterns. Our approach allowed bridging the gap between local (or metacommunity) and regional scales, providing key insights into drivers of regional biodiversity patterns.     

High spatial variability biases the space-for-time approach in environmental monitoring

The space-for-time approach is widely used in fundamental and applied ecology but assemblages from some habitats are highly variable. For example, streams may show marked spatio-temporal changes in the taxonomic composition of the macroinvertebrate assemblages. We exemplify the effect of the temporal component ‘season’ on some assemblage-derived stream quality assessment metrics under the assumptions of the space-for-time and the replicated samples approaches. Benthic macroinvertebrates were sampled in spring, summer, and fall from two stream types, namely streams in the Pleistocene sediments of the alpine foothills and small fine substrate dominated siliceous highland rivers in southern and central Germany. As exemplified for ASPT and the German multimetric index (MMI), the data showed no effect of season when samples were regarded as independent, whereas stream quality decreased between spring and fall in the replicated samples approach. The transformation of MMI to rank-ordered stream quality classes depicted a decrease in perceived stream quality in 29% and 54% of the sites by summer and early fall, respectively, when compared to spring samples. We thus suggest (1) to test seemingly robust metrics in a repetitive measures approach for other stream types and regions, and (2) to standardize the sampling season for ecological quality assessment. Based on this example, we assume that many subtle, but significant, environmental trends are still to be detected in highly heterogeneous habitats from various ecosystems.     

Deciphering the Origin of Interface-Induced High Li and Na Ion Conductivity in Nanocomposite Solid Electrolytes Using X-Ray Raman Spectroscopy

Solid-state electrolytes (SSEs) with high ionic conductivities are crucial for safer and high-capacity batteries. Interface effects in nanocomposites of SSEs and insulators can lead to profound increases in conductivity. Understanding the composition of the interface is crucial for tuning the conductivity of composite solid electrolytes. Herein, X-ray Raman Scattering (XRS) spectroscopy is used for the first time to unravel the nature of the interface effects responsible for conductivity enhancements in nanocomposites of complex hydride-based electrolytes (LiBH₄, NaBH₄, and NaNH₂) and oxides. XRS probe of the Li, Na, and B local environments reveals that the interface consists of highly distorted/defected and structurally distinct phase(s) compared to the original compounds. Interestingly, nanocomposites with higher concentrations of the interface compounds exhibit higher conductivities. Clear differences are observed in the interface composition of SiO₂- and Al₂O₃-based nanocomposites, attributed to differences in the reactivity of their surface groups. These results demonstrate that interfacial reactions play a dominant role in conductivity enhancement in composite solid electrolytes. This work showcases the potential of XRS in investigating interface interactions, providing valuable insights into the often complex ion conductor/insulator interfaces, especially for systems containing light elements such as Li, B, and Na present in most SSEs and batteries.     

Molecular Identification of Nanoplanktonic Protists Based on Small Subunit Ribosomal RNA Gene Sequences for Ecological Studies1

Nanoplanktonic protists are comprised of a diverse assemblage of species which are responsible for a variety of trophic processes in marine and freshwater ecosystems. Current methods for identifying small protists by electron microscopy do not readily permit both identification and enumeration of nanoplanktonic protists in field samples. Thus, one major goal in the application of molecular approaches in protistan ecology has been the detection and quantification of individual species in natural water samples. Sequences of small subunit ribosomal RNA (SSU rRNA) genes have proven to be useful towards achieving this goal. Comparison of sequences from clone libraries of protistan SSU rRNA genes amplified from natural assemblages of protists by the polymerase chain reaction (PCR) can be used to examine protistan diversity. Furthermore, oligonucleotide probes complementary to short sequence regions unique to species of small protists can be designed by comparative analysis of rRNA gene sequences. These probes may be used to either detect the RNA of particular species of protists in total nucleic acid extracts immobilized on membranes, or the presence of target species in water samples via in situ hybridization of whole cells. Oligonucleotide probes may also serve as primers for the selective amplification of target sequences from total population DNA by PCR. Thus, molecular sequence information is becoming increasingly useful for identifying and enumerating protists, and for studying their spatial and temporal distribution in nature. Knowledge of protistan species composition, abundance and variability in an environment can ultimately be used to relate community structure to various aspects of community function and biogeochemical activity.     

A series of 23,24-dihydrodiscodermolide analogues with simplified lactone regions

A collection of seven new 23,24-dihydrodiscodermolide analogues have been synthesized with modifications to the lactone ring, some of which show antiproliferative activities similar to discodermolide.     

Carcinoembryonic Antigen-Related Cell Adhesion Molecules (CEACAM) 1, 5 and 6 as Biomarkers in Pancreatic Cancer

Background

Aim of this study was to assess the biological function in tumor progression and metastatic process carcinoembryonic antigen-related cell adhesion molecules (CEACAM) 1, 5 and 6 in pancreatic adenocarcinoma (PDAC).

Experimental Design

CEACAM knock down cells were established and assessed in vitro and in a subcutaneous and intraperitoneal mouse xenograft model. Tissue and serum expression of patients with PDAC were assessed by immunohistochemistry (IHC) and by enzyme linked immunosorbent assays.

Results

Presence of lymph node metastasis was correlated with CEACAM 5 and 6 expression (determined by IHC) and tumor recurrence exclusively with CEACAM 6. Patients with CEACAM 5 and 6 expression showed a significantly shortened OS in Kaplan-Meier survival analyses. Elevated CEACAM6 serum values showed a correlation with distant metastasis and. Survival analysis revealed a prolonged OS for patients with low serum CEACAM 1 values. In vitro proliferation and migration capacity was increased in CEACAM knock down PDAC cells, however, mice inoculated with CEACAM knock down cells showed a prolonged overall-survival (OS). The number of spontaneous pulmonary metastasis was increased in the CEACAM knock down group.

Conclusion

The effects mediated by CEACAM expression in PDAC are complex, though overexpression is correlated with loco-regional aggressive tumor growth. However, loss of CEACAM can be considered as a part of epithelial-mesenchymal transition and is therefore of rather importance in the process of distant metastasis.     

Dispersal distance and the pool of taxa,but not barriers,determine the colonisation of restored river reaches by benthic invertebrates

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