142 research outputs found
Metaxa : a software tool for automated detection and discrimination among ribosomal small subunit (12S/16S/18S) sequences of archaea, bacteria, eukaryotes, mitochondria, and chloroplasts in metagenomes and environmental sequencing datasets
Peer reviewedPostprin
Teknisk kompetens hos tekniska projektledare i mjukvaruutvecklingsprojekt
Att arbeta i projektform inom mjukvaruutvecklingsbranschen har varit ett påstående som fått stöd ända sen branschens ursprungsdagar. Inom dessa projekt har rollen teknisk projektledare befästs. Rollen har ingen standardiserad innebörd men utgår i denna studie från en ledare som har ett övergripande ansvar för organisationens nyutveckling. Företag har historiskt sett tilldelat rollen teknisk projektledare till den mest tekniskt kompetenta inom företaget. Även om denna trend har kommit att förändras är det ännu oklart vilken nivå av teknisk kompetens som krävs av en teknisk projektledare. Genom att kombinera teorier om projektledning, mjukvaruutveckling samt kompetens med en kvalitativ undersökning redogör vi för teoretikers och branschspecialisters åsikter. Studiens syfte är att identifiera betydelsen av teknisk kompetens hos tekniska projektledare. Det som har framkommit från denna studie är att teknisk kompetens inte är en betydande faktor för att kunna axla rollen som teknisk projektledare. Men den tekniska kompetensen underlättar avsevärt kommunikationen med utvecklarna vilket kan vara betydande i företagsspecifika fall. Dessutom visar studien på att tillämpningen av de agila utvecklingsmetodikerna ställer nya krav på den tekniska projektledaren
Proteomic Evaluation of Neonatal Exposure to 2,2′,4,4′,5-Pentabromodiphenyl Ether
Exposure to the brominated flame retardant 2,2′,4,4′,5-pentabromodiphenyl ether (PBDE-99) during the brain growth spurt disrupts normal brain development in mice and results in disturbed spontaneous behavior in adulthood. The neurodevelopmental toxicity of PBDE-99 has been reported to affect the cholinergic and catecholaminergic systems. In this study we use a proteomics approach to study the early effect of PBDE-99 in two distinct regions of the neonatal mouse brain, the striatum and the hippocampus. A single oral dose of PBDE-99 (12 mg/kg body weight) or vehicle was administered to male NMRI mice on neonatal day 10, and the striatum and the hippocampus were isolated. Using two-dimensional fluorescence difference gel electrophoresis (2D-DIGE), we found 40 and 56 protein spots with significantly (p < 0.01) altered levels in the striatum and the hippocampus, respectively. We used matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI–ToF–MS) to determine the protein identity of 11 spots from the striatum and 10 from the hippocampus. We found that the levels of proteins involved in neurodegeneration and neuroplasticity (e.g., Gap-43/neuromodulin, stathmin) were typically altered in the striatum, and proteins involved in metabolism and energy production [e.g., α-enolase; γ-enolase; ATP synthase, H(+) transporting, mitochondrial F(1) complex, β subunit (Atp5b); and α-synuclein] were typically altered in the hippocampus. Interestingly, many of the identified proteins have been linked to protein kinase C signaling. In conclusion, we identify responses to early exposure to PBDE-99 that could contribute to persistent neurotoxic effects. This study also shows the usefulness of proteomics to identify potential biomarkers of developmental neurotoxicity of organohalogen compounds
Neuropeptidomic analysis of the embryonic Japanese quail diencephalon
<p>Abstract</p> <p>Background</p> <p>Endogenous peptides such as neuropeptides are involved in numerous biological processes in the fully developed brain but very little is known about their role in brain development. Japanese quail is a commonly used bird model for studying sexual dimorphic brain development, especially adult male copulatory behavior in relation to manipulations of the embryonic endocrine system. This study uses a label-free liquid chromatography mass spectrometry approach to analyze the influence of age (embryonic days 12 vs 17), sex and embryonic day 3 ethinylestradiol exposure on the expression of multiple endogenous peptides in the developing diencephalon.</p> <p>Results</p> <p>We identified a total of 65 peptides whereof 38 were sufficiently present in all groups for statistical analysis. Age was the most defining variable in the data and sex had the least impact. Most identified peptides were more highly expressed in embryonic day 17. The top candidates for EE<sub>2 </sub>exposure and sex effects were neuropeptide K (downregulated by EE<sub>2 </sub>in males and females), gastrin-releasing peptide (more highly expressed in control and EE<sub>2 </sub>exposed males) and gonadotropin-inhibiting hormone related protein 2 (more highly expressed in control males and displaying interaction effects between age and sex). We also report a new potential secretogranin-2 derived neuropeptide and previously unknown phosphorylations in the C-terminal flanking protachykinin 1 neuropeptide.</p> <p>Conclusions</p> <p>This study is the first larger study on endogenous peptides in the developing brain and implies a previously unknown role for a number of neuropeptides in middle to late avian embryogenesis. It demonstrates the power of label-free liquid chromatography mass spectrometry to analyze the expression of multiple endogenous peptides and the potential to detect new putative peptide candidates in a developmental model.</p
From tides to nucleotides: Genomic signatures of adaptation to environmental heterogeneity in barnacles
The northern acorn barnacle (Semibalanus balanoides) is a robust system to study the genetic basis of adaptations to highly heterogeneous environments. Adult barnacles may be exposed to highly dissimilar levels of thermal stress depending on where they settle in the intertidal (i.e., closer to the upper or lower tidal boundary). For instance, barnacles near the upper tidal limit experience episodic summer temperatures above recorded heat coma levels. This differential stress at the microhabitat level is also dependent on the aspect of sun exposure. In the present study, we used pool-seq approaches to conduct a genome wide screen for loci responding to intertidal zonation across the North Atlantic basin (Maine, Rhode Island, and Norway). Our analysis discovered 382 genomic regions containing SNPs which are consistently zonated (i.e., SNPs whose frequencies vary depending on their position in the rocky intertidal) across all surveyed habitats. Notably, most zonated SNPs are young and private to the North Atlantic. These regions show high levels of genetic differentiation across ecologically extreme microhabitats concomitant with elevated levels of genetic variation and Tajima's D, suggesting the action of non-neutral processes. Overall, these findings support the hypothesis that spatially heterogeneous selection is a general and repeatable feature for this species, and that natural selection can maintain functional genetic variation in heterogeneous environments.publishedVersio
Evolution from the Prokaryotic to the Higher Plant Chloroplast Signal Recognition Particle: The Signal Recognition Particle RNA Is Conserved in Plastids of a Wide Range of Photosynthetic Organisms
The protein targeting signal recognition particle (SRP) pathway in chloroplasts of higher plants has undergone dramatic evolutionary changes. It disposed of its RNA, which is an essential SRP component in bacteria, and uses a unique chloroplast-specific protein cpSRP43. Nevertheless, homologs of the conserved SRP54 and the SRP receptor, FtsY, are present in higher plant chloroplasts. In this study, we analyzed the phylogenetic distribution of SRP components in photosynthetic organisms to elucidate the evolution of the SRP system. We identified conserved plastid SRP RNAs within all nonspermatophyte land plant lineages and in all chlorophyte branches. Furthermore, we show the simultaneous presence of cpSRP43 in these organisms. The function of this novel SRP system was biochemically and structurally characterized in the moss Physcomitrella patens. We show that P. patens chloroplast SRP (cpSRP) RNA binds cpSRP54 but has lost the ability to significantly stimulate the GTPase cycle of SRP54 and FtsY. Furthermore, the crystal structure at 1.8-Å resolution and the nucleotide specificity of P. patens cpFtsY was determined and compared with bacterial FtsY and higher plant chloroplast FtsY. Our data lead to the view that the P. patens cpSRP system occupies an intermediate position in the evolution from bacterial-type SRP to higher plant-type cpSRP system
Rapid cross-border emergence of NDM-5-producing Escherichia coli in the European Union/European Economic Area, 2012 to June 2022
Whole genome sequencing data of 874 Escherichia
coli isolates carrying blaNDM-5 from 13 European Union/
European Economic Area countries between 2012 and
June 2022 showed the predominance of sequence
types ST167, ST405, ST410, ST361 and ST648, and
an increasing frequency of detection. Nearly a third
(30.6%) of these isolates were associated with
infections and more than half (58.2%) were predicted
to be multidrug-resistant. Further spread of E.
coli carrying blaNDM-5 would leave limited treatment
options for serious E. coli infections
Cross-border spread of blaNDM-1- and blaOXA-48-positive Klebsiella pneumoniae: a European collaborative analysis of whole genome sequencing and epidemiological data, 2014 to 2019
An alert regarding an outbreak of carbapenem-resistant Klebsiella pneumoniae carrying bla NDM-1 and bla OXA-48 carbapenemase-encoding genes was sent by Germany to European Union (EU)/European Economic Area (EEA) countries in October 2019. Since only limited whole genome sequencing (WGS) data on bla NDM-1- and bla OXA-48-positive K. pneumoniae were available in the public domain, national public health reference or equivalent expert laboratories from EU/EEA countries were invited to share WGS data from their national collections with the European Centre for Disease Prevention and Control (ECDC) to investigate the international dissemination of this epidemic strain. The analysis identified a Finnish case with an isolate closely related to the German outbreak strain and with an epidemiological link to St. Petersburg, Russia. In addition, several other clusters of genetically related bla NDM-1- and bla OXA-48-positive K. pneumoniae unrelated to the German outbreak strain but affecting numerous EU/EEA countries were identified. The aim of this follow-up investigation was to characterise these clusters based on the integrated analysis of the WGS dataset on bla NDM-1 - and bla OXA-48-positive K. pneumoniae submitted from 13 EU/EEA countries and additional epidemiological data
EEG Data Quality: Determinants and Impact in a Multicenter Study of Children, Adolescents, and Adults with Attention-Deficit/Hyperactivity Disorder (ADHD)
Electroencephalography (EEG) represents a widely established method for assessing altered and typically developing brain function. However, systematic studies on EEG data quality, its
correlates, and consequences are scarce. To address this research gap, the current study focused on
the percentage of artifact-free segments after standard EEG pre-processing as a data quality index.
We analyzed participant-related and methodological influences, and validity by replicating landmark
EEG effects. Further, effects of data quality on spectral power analyses beyond participant-related
characteristics were explored. EEG data from a multicenter ADHD-cohort (age range 6 to 45 years),
and a non-ADHD school-age control group were analyzed (ntotal = 305). Resting-state data during
eyes open, and eyes closed conditions, and task-related data during a cued Continuous Performance
Task (CPT) were collected. After pre-processing, general linear models, and stepwise regression
models were fitted to the data. We found that EEG data quality was strongly related to demographic
characteristics, but not to methodological factors. We were able to replicate maturational, task,
and ADHD effects reported in the EEG literature, establishing a link with EEG-landmark effects.
Furthermore, we showed that poor data quality significantly increases spectral power beyond effects of maturation and symptom severity. Taken together, the current results indicate that with
a careful design and systematic quality control, informative large-scale multicenter trials characterizing neurophysiological mechanisms in neurodevelopmental disorders across the lifespan are
feasible. Nevertheless, results are restricted to the limitations reported. Future work will clarify
predictive value
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