124 research outputs found

    How clear is our current view on microbial dark matter? (Re-)assessing public MAG & SAG datasets with MDMcleaner

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    As of today, the majority of environmental microorganisms remain uncultured and is therefore referred to as ‘microbial dark matter’ (MDM). Hence, genomic insights into these organisms are limited to cultivation-independent approaches such as single-cell- and metagenomics. However, without access to cultured representatives for verifying correct taxon-assignments, MDM genomes may cause potentially misleading conclusions based on misclassified or contaminant contigs, thereby obfuscating our view on the uncultured microbial majority. Moreover, gradual database contaminations by past genome submissions can cause error propagations which affect present as well as future comparative genome analyses. Consequently, strict contamination detection and filtering need to be applied, especially in the case of uncultured MDM genomes. Current genome reporting standards, however, emphasize completeness over purity and the de facto gold standard genome assessment tool, checkM, discriminates against uncultured taxa and fragmented genomes. To tackle these issues, we present a novel contig classification, screening, and filtering workflow and corresponding open-source python implementation called MDMcleaner, which was tested and compared to other tools on mock and real datasets. MDMcleaner revealed substantial contaminations overlooked by current screening approaches and sensitively detects misattributed contigs in both novel genomes and the underlying reference databases, thereby greatly improving our view on ‘microbial dark matter’

    German Screen for Child Anxiety Related Emotional Disorders (SCARED): Reliability, Validity, and Cross-Informant Agreement in a Clinical Sample

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    <p>Abstract</p> <p>Background</p> <p>The psychometric properties and cross-informant agreement of a German translation of the Screen for Child Anxiety Related Emotional Disorders (SCARED) were assessed in a clinical sample</p> <p>Methods</p> <p>102 children and adolescents in outpatient psychotherapy and their parents filled out the SCARED and Youth Self Report/Child Behaviour Checklist (YSR/CBCL).</p> <p>Results</p> <p>The German SCARED showed good internal consistency for both parent and self-report version, and proved to be convergently and discriminantly valid when compared with YSR/CBCL scales. Cross-informant agreement was moderate with children reporting both a larger number as well as higher severity of anxiety symptoms than their parents.</p> <p>Conclusion</p> <p>In conclusion, the German SCARED is a valid and reliable anxiety scale and may be used in a clinical setting</p

    Printing Microbial Dark Matter: Using Single Cell Dispensing and Genomics to Investigate the Patescibacteria/Candidate Phyla Radiation

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    As of today, the majority of environmental microorganisms remain uncultured. They are therefore referred to as “microbial dark matter.” In the recent past, cultivation-independent methods like single-cell genomics (SCG) enabled the discovery of many previously unknown microorganisms, among them the Patescibacteria/Candidate Phyla Radiation (CPR). This approach was shown to be complementary to metagenomics, however, the development of additional and refined sorting techniques beyond the most commonly used fluorescence-activated cell sorting (FACS) is still desirable to enable additional downstream applications. Adding image information on the number and morphology of sorted cells would be beneficial, as would be minimizing cell stress caused by sorting conditions such as staining or pressure. Recently, a novel cell sorting technique has been developed, a microfluidic single-cell dispenser, which assesses the number and morphology of the cell in each droplet by automated light microscopic processing. Here, we report for the first time the successful application of the newly developed single-cell dispensing system for label-free isolation of individual bacteria from a complex sample retrieved from a wastewater treatment plant, demonstrating the potential of this technique for single cell genomics and other alternative downstream applications. Genome recovery success rated above 80% with this technique—out of 880 sorted cells 717 were successfully amplified. For 50.1% of these, analysis of the 16S rRNA gene was feasible and led to the sequencing of 50 sorted cells identified as Patescibacteria/CPR members. Subsequentially, 27 single amplified genomes (SAGs) of 15 novel and distinct Patescibacteria/CPR members, representing yet unseen species, genera and families could be captured and reconstructed. This phylogenetic distinctness of the recovered SAGs from available metagenome-assembled genomes (MAGs) is accompanied by the finding that these lineages—in whole or in part—have not been accessed by genome-resolved metagenomics of the same sample, thereby emphasizing the importance and opportunities of SCGs

    Mucisphaera calidilacus gen. nov., sp. nov., a novel planctomycete of the class Phycisphaerae isolated in the shallow sea hydrothermal system of the Lipari Islands

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    For extending the current collection of axenic cultures of planctomycetes, we describe in this study the isolation and characterisation of strain Pan265(T) obtained from a red biofilm in the hydrothermal vent system close to the Lipari Islands in the Tyrrhenian Sea, north of Sicily, Italy. The strain forms light pink colonies on solid medium and grows as a viscous colloid in liquid culture, likely as the result of formation of a dense extracellular matrix observed during electron microscopy. Cells of the novel isolate are spherical, motile and divide by binary fission. Strain Pan265(T) is mesophilic (temperature optimum 30–33 °C), neutrophilic (pH optimum 7.0–8.0), aerobic and heterotrophic. The strain has a genome size of 3.49 Mb and a DNA G + C content of 63.9%. Phylogenetically, the strain belongs to the family Phycisphaeraceae, order Phycisphaerales, class Phycisphaerae. Our polyphasic analysis supports the delineation of strain Pan265(T) from the known genera in this family. Therefore, we conclude to assign strain Pan265(T) to a novel species within a novel genus, for which we propose the name Mucisphaera calidilacus gen. nov., sp. nov. The novel species is the type species of the novel genus and is represented by strain Pan265(T) (= DSM 100697(T) = CECT 30425(T)) as type strain

    Description of Polystyrenella longa gen. nov., sp. nov., isolated from polystyrene particles incubated in the Baltic Sea

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    Planctomycetes occur in almost all aquatic ecosystems on earth. They have a remarkable cell biology, and members of the orders Planctomycetales and Pirellulales feature cell division by polar budding, perform a lifestyle switch from sessile to motile cells and have an enlarged periplasmic space. Here, we characterise a novel planctomycetal strain, Pla110τ^{τ}, isolated from the surface of polystyrene particles incubated in the Baltic Sea. After phylogenetic analysis, the strain could be placed in the family Planctomycetaceae. Strain Pla110τ^{τ} performs cell division by budding, has crateriform structures and grows in aggregates or rosettes. The strain is a chemoheterotroph, grows under mesophilic and neutrophilic conditions, and exhibited a doubling time of 21 h. Based on our phylogenetic and morphological characterisation, strain Pla110τ^{τ} (DSM 103387τ^{τ} = LMG 29693τ^{τ}) is concluded to represent a novel species belonging to a novel genus, for which we propose the name Polystyrenella longa gen. nov., sp. nov

    Tautonia plasticadhaerens sp. nov., a novel species in the family Isosphaeraceae isolated from an alga in a hydrothermal area of the Eolian Archipelago

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    A novel planctomycetal strain, designated ElPT^{T}, was isolated from an alga in the shallow hydrothermal vent system close to Panarea Island in the Tyrrhenian Sea. Cells of strain ElPT^{T} are spherical, form pink colonies and display typical planctomycetal characteristics including division by budding and presence of crateriform structures. Strain ElPT^{T} has a mesophilic (optimum at 30 °C) and neutrophilic (optimum at pH 7.5) growth profile, is aerobic and heterotrophic. It reaches a generation time of 29 h (ÎŒmax_{max} = 0.024 h−1^{-1}). The strain has a genome size of 9.40 Mb with a G + C content of 71.1% and harbours five plasmids, the highest number observed in the phylumPlanctomycetes thus far. Phylogenetically, the strain represents a novel species of the recently described genus Tautonia in the family Isosphaeraceae. A characteristic feature of the strain is ist tendency to attach strongly to a range of plastic surfaces. We thus propose the name Tautonia plasticadhaerens sp. nov. for the novel species, represented by the type strain ElPT^{T} (DSM 101012T^{T} = LMG 29141T^{T})

    Standardized Diagnostics Including PET-CT Imaging, Bilateral Tonsillectomy and Neck Dissection Followed by Risk-Adapted Post-Operative Treatment Favoring Radio-Chemotherapy Improve Survival of Neck Squamous Cell Carcinoma of Unknown Primary Patients

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    Background: About five to 10% of cancers in the head and neck region are neck squamous cell carcinoma of unknown primary (NSCCUP). Their diagnosis and treatment are challenging given the risk of missing occult tumors and potential relapse. Recently, we described human papillomavirus (HPV)-related NSCCUP-patients (NSCCUP-P) as a subgroup with superior survival. However, standardized diagnostic workup, novel diagnostic procedures, decision-making in the multidisciplinary tumor board (MDTB) and multimodal therapy including surgery and post-operative radio-chemotherapy (PORCT) may also improve survival. Methods: For assessing the impact of standardized diagnostic processes simultaneously established with the MDTB on outcome, we split our sample of 115 NSCCUP-P into two cohorts treated with curative intent from 1988 to 2006 (cohort 1; n = 53) and 2007 to 2018 (cohort 2; n = 62). We compared diagnostic processes and utilized treatment modalities applying Chi-square tests, and outcome by Kaplan–Meier plots and Cox regression. Results: In cohort 2, the standardized processes (regular use of [18F]-FDG-PET-CT imaging followed by examination under anesthesia, EUA, bilateral tonsillectomy and neck dissection, ND, at least of the affected site) improved detection of primaries (P = 0.026) mostly located in the oropharynx (P = 0.001). From 66.0 to 87.1% increased ND frequency (P = 0.007) increased the detection of extracapsular extension of neck nodes (ECE+) forcing risk factor-adapted treatment by increased utilization of cisplatin-based PORCT that improved 5-years progression-free and overall survival from 60.4 and 45.3 to 67.7% (P = 0.411) and 66.1% (P = 0.025). Conclusions: Standardized diagnostic workup followed by ND and risk-factor adapted therapy improves survival of NSCCUP-P
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