108 research outputs found
Roe deer (Capreolus capreolus) are a novel potential reservoir for human visceral leishmaniasis in the Emilia-Romagna region of northeastern Italy
Leishmaniasis is a complex human disease caused by intracellular parasites of the genus Leishmania, predominantly transmitted by the bite of sand flies. In Italy, leishmaniasis is caused exclusively by Leishmania infantum, responsible for the human and canine visceral leishmaniases (HVL and CVL, respectively). Within the Emilia-Romagna region, two different foci are active in the municipalities of Pianoro and Valsamoggia (both in the province of Bologna). Recent molecular studies indicated that L. infantum strains circulating in dogs and humans are different, suggesting that there is an animal reservoir other than dogs for human visceral leishmaniasis in the Emilia-Romagna region. In this work, we analyzed specimens from wild animals collected during hunts or surveillance of regional parks near active foci of human visceral leishmaniasis for L. infantum infection in the province of Bologna. Out of 70 individuals analyzed, 17 (24%) were positive for L. infantum. The infection prevalence in hedgehogs (Erinaceus europaeus), roe deer (Capreolus capreolus), badgers (Meles meles), and bank voles (Myodes glareolus) was 80, 33, 25, and 11%, respectively. To distinguish the two strains of L. infantum we have developed a nested PCR protocol optimized for animal tissues. Our results demonstrated that most (over 90%) of L. infantum infections in roe deer were due to the strain circulating in humans in the Emilia-Romagna region
Genome of Ca. Pandoraea novymonadis, an Endosymbiotic Bacterium of the Trypanosomatid Novymonas esmeraldas
We have sequenced, annotated, and analyzed the genome of Ca. Pandoraea novymonadis, a recently described bacterial endosymbiont of the trypanosomatid Novymonas esmeraldas. When compared with genomes of its free-living relatives, it has all the hallmarks of the endosymbionts’ genomes, such as significantly reduced size, extensive gene loss, low GC content, numerous gene rearrangements, and low codon usage bias. In addition, Ca. P. novymonadis lacks mobile elements, has a strikingly low number of pseudogenes, and almost all genes are single copied. This suggests that it already passed the intensive period of host adaptation, which still can be observed in the genome of Polynucleobacter necessarius, a certainly recent endosymbiont. Phylogenetically, Ca. P. novymonadis is more related to P. necessarius, an intracytoplasmic bacterium of free-living ciliates, than to Ca. Kinetoplastibacterium spp., the only other known endosymbionts of trypanosomatid flagellates. As judged by the extent of the overall genome reduction and the loss of particular metabolic abilities correlating with the increasing dependence of the symbiont on its host, Ca. P. novymonadis occupies an intermediate position P. necessarius and Ca. Kinetoplastibacterium spp. We conclude that the relationships between Ca. P. novymonadis and N. esmeraldas are well-established, although not as fine-tuned as in the case of Strigomonadinae and their endosymbionts
Viral discovery and diversity in trypanosomatid protozoa with a focus on relatives of the human parasite <i>Leishmania</i>.
Knowledge of viral diversity is expanding greatly, but many lineages remain underexplored. We surveyed RNA viruses in 52 cultured monoxenous relatives of the human parasite <i>Leishmania</i> ( <i>Crithidia</i> and <i>Leptomonas</i> ), as well as plant-infecting <i>Phytomonas</i> <i>Leptomonas pyrrhocoris</i> was a hotbed for viral discovery, carrying a virus (Leptomonas pyrrhocoris ostravirus 1) with a highly divergent RNA-dependent RNA polymerase missed by conventional BLAST searches, an emergent clade of tombus-like viruses, and an example of viral endogenization. A deep-branching clade of trypanosomatid narnaviruses was found, notable as <i>Leptomonas seymouri</i> bearing Narna-like virus 1 (LepseyNLV1) have been reported in cultures recovered from patients with visceral leishmaniasis. A deep-branching trypanosomatid viral lineage showing strong affinities to bunyaviruses was termed " <i>Leishbunyavirus</i> " (LBV) and judged sufficiently distinct to warrant assignment within a proposed family termed " <i>Leishbunyaviridae</i> " Numerous relatives of trypanosomatid viruses were found in insect metatranscriptomic surveys, which likely arise from trypanosomatid microbiota. Despite extensive sampling we found no relatives of the totivirus <i>Leishmaniavirus</i> (LRV1/2), implying that it was acquired at about the same time the <i>Leishmania</i> became able to parasitize vertebrates. As viruses were found in over a quarter of isolates tested, many more are likely to be found in the >600 unsurveyed trypanosomatid species. Viral loss was occasionally observed in culture, providing potentially isogenic virus-free lines enabling studies probing the biological role of trypanosomatid viruses. These data shed important insights on the emergence of viruses within an important trypanosomatid clade relevant to human disease
Biotic interactions as drivers of algal origin and evolution
Biotic interactions underlie life's diversity and are the lynchpin to understanding its complexity and resilience within an ecological niche. Algal biologists have embraced this paradigm, and studies building on the explosive growth in omics and cell biology methods have facilitated the in-depth analysis of nonmodel organisms and communities from a variety of ecosystems. In turn, these advances have enabled a major revision of our understanding of the origin and evolution of photosynthesis in eukaryotes, bacterial–algal interactions, control of massive algal blooms in the ocean, and the maintenance and degradation of coral reefs. Here, we review some of the most exciting developments in the field of algal biotic interactions and identify challenges for scientists in the coming years. We foresee the development of an algal knowledgebase that integrates ecosystem-wide omics data and the development of molecular tools/resources to perform functional analyses of individuals in isolation and in populations. These assets will allow us to move beyond mechanistic studies of a single species towards understanding the interactions amongst algae and other organisms in both the laboratory and the field
CRITERION ANTIWEAR CHARACTERISTICS OF LUBRICATION OILS
It was suggested a new conception of identification of wear intensity of lubricated steel friction surfaces by size and distribut6ion of micromechanical characteristics in thin undersurface level, deformated by friction. Suggested criterion characterize antiwear features of lubrication oils
Insect trypanosomatids in Papua New Guinea: high endemism and diversity (18S rRNA dataset)
We analyzed the collection of heteropteran hosts (907 specimens from 138 species and 23 families) captured in Papua New Guinea (PNG), a well-known biodiversity hotspot with a considerable number of endemic species of macroorganisms, for the presence of trypanosomatids, the prevalence of infection and host specificity. In addition to discovery of numerous new parasite species, some of which may represent new trypanosomatid genera, we recorded new insect hosts for the widespread trypanosomatid species and revealed potential cases of host-parasite coevolution.
Attached is the alignment of sequences used in our assay of trypanosomatid diversity in PNG.
In total, 185 trypanosomatid 18S rRNA sequences (147 retrieved from the GenBank and 38 representing typing units unique for PNG) were aligned using MAFFT v. 7.4. Alignment trimming was not performed in order to preserve differences between closely related species
Provenance discrimination in sediments from the Mendeleev Ridge (Central Arctic Ocean): implications for reconstructions of sediment sources and pathways over the last 200,000 years
Provenance discrimination in sediments from the Mendeleev Ridge (Central Arctic Ocean): implications for reconstructions of sediment sources and pathways over the last 200,000 years
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