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1.
Nature ; 595(7868): 565-571, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34153974

RESUMEN

Although SARS-CoV-2 primarily targets the respiratory system, patients with and survivors of COVID-19 can suffer neurological symptoms1-3. However, an unbiased understanding of the cellular and molecular processes that are affected in the brains of patients with COVID-19 is missing. Here we profile 65,309 single-nucleus transcriptomes from 30 frontal cortex and choroid plexus samples across 14 control individuals (including 1 patient with terminal influenza) and 8 patients with COVID-19. Although our systematic analysis yields no molecular traces of SARS-CoV-2 in the brain, we observe broad cellular perturbations indicating that barrier cells of the choroid plexus sense and relay peripheral inflammation into the brain and show that peripheral T cells infiltrate the parenchyma. We discover microglia and astrocyte subpopulations associated with COVID-19 that share features with pathological cell states that have previously been reported in human neurodegenerative disease4-6. Synaptic signalling of upper-layer excitatory neurons-which are evolutionarily expanded in humans7 and linked to cognitive function8-is preferentially affected in COVID-19. Across cell types, perturbations associated with COVID-19 overlap with those found in chronic brain disorders and reside in genetic variants associated with cognition, schizophrenia and depression. Our findings and public dataset provide a molecular framework to understand current observations of COVID-19-related neurological disease, and any such disease that may emerge at a later date.


Asunto(s)
Astrocitos/patología , Encéfalo/patología , COVID-19/diagnóstico , COVID-19/patología , Plexo Coroideo/patología , Microglía/patología , Neuronas/patología , Anciano , Anciano de 80 o más Años , Encéfalo/metabolismo , Encéfalo/fisiopatología , Encéfalo/virología , COVID-19/genética , COVID-19/fisiopatología , Núcleo Celular/genética , Plexo Coroideo/metabolismo , Plexo Coroideo/fisiopatología , Plexo Coroideo/virología , Femenino , Humanos , Inflamación/virología , Masculino , Persona de Mediana Edad , SARS-CoV-2/crecimiento & desarrollo , SARS-CoV-2/patogenicidad , Análisis de la Célula Individual , Transcriptoma , Replicación Viral
2.
Nucleic Acids Res ; 52(D1): D579-D585, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-37994699

RESUMEN

The human microbiome has emerged as a rich source of diverse and bioactive natural products, harboring immense potential for therapeutic applications. To facilitate systematic exploration and analysis of its biosynthetic landscape, we present ABC-HuMi: the Atlas of Biosynthetic Gene Clusters (BGCs) in the Human Microbiome. ABC-HuMi integrates data from major human microbiome sequence databases and provides an expansive repository of BGCs compared to the limited coverage offered by existing resources. Employing state-of-the-art BGC prediction and analysis tools, our database ensures accurate annotation and enhanced prediction capabilities. ABC-HuMi empowers researchers with advanced browsing, filtering, and search functionality, enabling efficient exploration of the resource. At present, ABC-HuMi boasts a catalog of 19 218 representative BGCs derived from the human gut, oral, skin, respiratory and urogenital systems. By capturing the intricate biosynthetic potential across diverse human body sites, our database fosters profound insights into the molecular repertoire encoded within the human microbiome and offers a comprehensive resource for the discovery and characterization of novel bioactive compounds. The database is freely accessible at https://www.ccb.uni-saarland.de/abc_humi/.


Asunto(s)
Vías Biosintéticas , Bases de Datos Genéticas , Microbiota , Familia de Multigenes , Humanos , Vías Biosintéticas/genética , Biología Computacional/instrumentación , Internet , Microbiota/genética , Familia de Multigenes/genética , Metagenoma/genética
3.
Nucleic Acids Res ; 52(W1): W407-W414, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38716863

RESUMEN

Quantifying microbiome species and composition from metagenomic assays is often challenging due to its time-consuming nature and computational complexity. In Bioinformatics, k-mer-based approaches were long established to expedite the analysis of large sequencing data and are now widely used to annotate metagenomic data. We make use of k-mer counting techniques for efficient and accurate compositional analysis of microbiota from whole metagenome sequencing. Mibianto solves this problem by operating directly on read files, without manual preprocessing or complete data exchange. It handles diverse sequencing platforms, including short single-end, paired-end, and long read technologies. Our sketch-based workflow significantly reduces the data volume transferred from the user to the server (up to 99.59% size reduction) to subsequently perform taxonomic profiling with enhanced efficiency and privacy. Mibianto offers functionality beyond k-mer quantification; it supports advanced community composition estimation, including diversity, ordination, and differential abundance analysis. Our tool aids in the standardization of computational workflows, thus supporting reproducibility of scientific sequencing studies. It is adaptable to small- and large-scale experimental designs and offers a user-friendly interface, thus making it an invaluable tool for both clinical and research-oriented metagenomic studies. Mibianto is freely available without the need for a login at: https://www.ccb.uni-saarland.de/mibianto.


Asunto(s)
Metagenómica , Microbiota , Programas Informáticos , Metagenómica/métodos , Microbiota/genética , Humanos , Metagenoma , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Internet , Flujo de Trabajo , Análisis de Secuencia de ADN/métodos , Biología Computacional/métodos
4.
Nucleic Acids Res ; 51(W1): W319-W325, 2023 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-37177999

RESUMEN

MicroRNAs (miRNAs) are small non-coding RNAs that play a critical role in regulating diverse biological processes. Extracting functional insights from a list of miRNAs is challenging, as each miRNA can potentially interact with hundreds of genes. To address this challenge, we developed miEAA, a flexible and comprehensive miRNA enrichment analysis tool based on direct and indirect miRNA annotation. The latest release of miEAA includes a data warehouse of 19 miRNA repositories, covering 10 different organisms and 139 399 functional categories. We have added information on the cellular context of miRNAs, isomiRs, and high-confidence miRNAs to improve the accuracy of the results. We have also improved the representation of aggregated results, including interactive Upset plots to aid users in understanding the interaction among enriched terms or categories. Finally, we demonstrate the functionality of miEAA in the context of ageing and highlight the importance of carefully considering the miRNA input list. MiEAA is free to use and publicly available at https://www.ccb.uni-saarland.de/mieaa/.


Asunto(s)
MicroARNs , Programas Informáticos , MicroARNs/genética , Bases de Datos de Ácidos Nucleicos
5.
Nucleic Acids Res ; 51(D1): D179-D185, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36243964

RESUMEN

A significant fraction of mature miRNA transcripts carries sequence and/or length variations, termed isomiRs. IsomiRs are differentially abundant in cell types, tissues, body fluids or patients' samples. Not surprisingly, multiple studies describe a physiological and pathophysiological role. Despite their importance, systematically collected and annotated isomiR information available in databases remains limited. We thus developed isomiRdb, a comprehensive resource that compiles miRNA expression data at isomiR resolution from various sources. We processed 42 499 human miRNA-seq datasets (5.9 × 1011 sequencing reads) and consistently analyzed them using miRMaster and sRNAbench. Our database provides online access to the 90 483 most abundant isomiRs (>1 RPM in at least 1% of the samples) from 52 tissues and 188 cell types. Additionally, the full set of over 3 million detected isomiRs is available for download. Our resource can be queried at the sample, miRNA or isomiR level so users can quickly answer common questions about the presence/absence of a particular miRNA/isomiR in tissues of interest. Further, the database facilitates to identify whether a potentially interesting new isoform has been detected before and its frequency. In addition to expression tables, isomiRdb can generate multiple interactive visualisations including violin plots and heatmaps. isomiRdb is free to use and publicly available at: https://www.ccb.uni-saarland.de/isomirdb.


Asunto(s)
Bases de Datos Genéticas , MicroARNs , Humanos , Secuenciación de Nucleótidos de Alto Rendimiento , MicroARNs/genética , MicroARNs/metabolismo , Isoformas de Proteínas/genética , Análisis de Secuencia de ARN
6.
RNA Biol ; 21(1): 31-44, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38828710

RESUMEN

Non-thermal plasma, a partially ionized gas, holds significant potential for clinical applications, including wound-healing support, oral therapies, and anti-tumour treatments. While its applications showed promising outcomes, the underlying molecular mechanisms remain incompletely understood. We thus apply non-thermal plasma to mouse auricular skin and conducted non-coding RNA sequencing, as well as single-cell blood sequencing. In a time-series analysis (five timepoints spanning 2 hours), we compare the expression of microRNAs in the plasma-treated left ears to the unexposed right ears of the same mice as well as to the ears of unexposed control mice. Our findings indicate specific effects in the treated ears for a set of five miRNAs: mmu-miR-144-5p, mmu-miR-144-3p, mmu-miR-142a-5p, mmu-miR-223-3p, and mmu-miR-451a. Interestingly, mmu-miR-223-3p also exhibits an increase over time in the right non-treated ear of the exposed mice, suggesting systemic effects. Notably, this miRNA, along with mmu-miR-142a-5p and mmu-miR-144-3p, regulates genes and pathways associated with wound healing and tissue regeneration (namely ErbB, FoxO, Hippo, and PI3K-Akt signalling). This co-regulation is particularly remarkable considering the significant seed dissimilarities among the miRNAs. Finally, single-cell sequencing of PBMCs reveals the downregulation of 12 from 15 target genes in B-cells, Cd4+ and Cd8+ T-cells. Collectively, our data provide evidence for a systemic effect of non-thermal plasma.


Asunto(s)
Regulación de la Expresión Génica , MicroARNs , Gases em Plasma , Piel , MicroARNs/genética , Animales , Ratones , Piel/metabolismo , Gases em Plasma/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Perfilación de la Expresión Génica , Cicatrización de Heridas/efectos de los fármacos , Transducción de Señal , Sistema Inmunológico/metabolismo
7.
Nucleic Acids Res ; 50(W1): W132-W137, 2022 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-35489067

RESUMEN

Despite recent methodology and reference database improvements for taxonomic profiling tools, metagenomic assembly and genomic binning remain important pillars of metagenomic analysis workflows. In case reference information is lacking, genomic binning is considered to be a state-of-the-art method in mixed culture metagenomic data analysis. In this light, our previously published tool BusyBee Web implements a composition-based binning method efficient enough to function as a rapid online utility. Handling assembled contigs and long nanopore generated reads alike, the webserver provides a wide range of supplementary annotations and visualizations. Half a decade after the initial publication, we revisited existing functionality, added comprehensive visualizations, and increased the number of data analysis customization options for further experimentation. The webserver now allows for visualization-supported differential analysis of samples, which is computationally expensive and typically only performed in coverage-based binning methods. Further, users may now optionally check their uploaded samples for plasmid sequences using PLSDB as a reference database. Lastly, a new application programming interface with a supporting python package was implemented, to allow power users fully automated access to the resource and integration into existing workflows. The webserver is freely available under: https://www.ccb.uni-saarland.de/busybee.


Asunto(s)
Algoritmos , Metagenoma , Programas Informáticos , Metagenómica/métodos , Flujo de Trabajo , Análisis de Secuencia de ADN
8.
Nucleic Acids Res ; 50(D1): D273-D278, 2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34850116

RESUMEN

Plasmids are known to contain genes encoding for virulence factors and antibiotic resistance mechanisms. Their relevance in metagenomic data processing is steadily growing. However, with the increasing popularity and scale of metagenomics experiments, the number of reported plasmids is rapidly growing as well, amassing a considerable number of false positives due to undetected misassembles. Here, our previously published database PLSDB provides a reliable resource for researchers to quickly compare their sequences against selected and annotated previous findings. Within two years, the size of this resource has more than doubled from the initial 13,789 to now 34,513 entries over the course of eight regular data updates. For this update, we aggregated community feedback for major changes to the database featuring new analysis functionality as well as performance, quality, and accessibility improvements. New filtering steps, annotations, and preprocessing of existing records improve the quality of the provided data. Additionally, new features implemented in the web-server ease user interaction and allow for a deeper understanding of custom uploaded sequences, by visualizing similarity information. Lastly, an application programming interface was implemented along with a python library, to allow remote database queries in automated workflows. The latest release of PLSDB is freely accessible under https://www.ccb.uni-saarland.de/plsdb.


Asunto(s)
Bacterias/genética , Bases de Datos Genéticas , Plásmidos/química , Interfaz Usuario-Computador , Actinobacteria/genética , Actinobacteria/patogenicidad , Bacterias/clasificación , Bacterias/patogenicidad , Bacteroidetes/genética , Bacteroidetes/patogenicidad , Farmacorresistencia Microbiana/genética , Firmicutes/genética , Firmicutes/patogenicidad , Internet , Metagenómica/métodos , Anotación de Secuencia Molecular , Plásmidos/clasificación , Plásmidos/metabolismo , Proteobacteria/genética , Proteobacteria/patogenicidad , Spirochaetales/genética , Spirochaetales/patogenicidad , Tenericutes/genética , Tenericutes/patogenicidad , Virulencia/genética
9.
Opt Express ; 31(8): 12693-12702, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37157425

RESUMEN

We characterize the intensity noise of two mid-infrared (MIR) ultrafast tunable (3.5-11 µm) sources based on difference frequency generation (DFG). While both sources are pumped by a high repetition rate Yb-doped amplifier delivering 200 µJ 300 fs at a central wavelength of 1030 nm, the first is based on intrapulse DFG (intraDFG), and the second on DFG at the output of an optical parametric amplifier (OPA). The noise properties are assessed through measurement of the relative intensity noise (RIN) power spectral density and pulse-to-pulse stability. The noise transfer mechanisms from the pump to the MIR beam is empirically demonstrated. As an example, improving the pump laser noise performance allows reduction of the integrated RIN (IRIN) of one of the MIR source from 2.7% RMS down to 0.4% RMS. The intensity noise is also measured at various stages and in several wavelength ranges in both laser system architectures, allowing us to identify the physical origin of their variation. This study presents numerical values for the pulse to pulse stability, and analyze the frequency content of the RINs of particular importance for the design of low-noise high repetition rate tunable MIR sources and future high performance time-resolved molecular spectroscopy experiments.

10.
J Urol ; 207(3): 551-558, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34694143

RESUMEN

PURPOSE: While lymph node dissection (LND) at radical cystectomy (RC) for muscle-invasive bladder cancer has been studied extensively, the role of LND for nonmuscle-invasive bladder cancer (NMIBC) remains incompletely defined. Herein, we aim to assess the association between extent of LND during RC for NMIBC and local pelvic recurrence-free survival (LPRS), cancer-specific survival (CSS) and overall survival (OS). MATERIALS AND METHODS: A multi-institutional retrospective review was performed of patients with NMIBC undergoing RC at 3 large tertiary referral centers. To identify a threshold for lymph node yield (LNY) to optimize LPRS, CSS and OS, separate Cox regression models were developed for each possible LNY threshold. Model performance including Q-statistics and hazard ratios (HRs) were used to identify optimal LNY thresholds. RESULTS: A total of 1,647 patients underwent RC for NMIBC, with a median LNY of 15 (quartiles 9,23). Model performance curves suggested LNY of 10 and 20 to optimize LPRS and CSS/OS, respectively. On multivariable regression, LNY >10 was associated with lower risk of LPR compared to LNY ≤10 (HR 0.63, 95% CI 0.42-0.93, p=0.02). Similarly, LNY >20 was associated with improved CSS (HR 0.67, 95% CI 0.52-0.87, p=0.002) and OS (HR 0.75, 95% CI 0.64-0.88, p <0.001) compared to LNY ≤20. Similar results were observed in the cT1 and cTis subgroups. CONCLUSIONS: Greater extent of LND during RC for NMIBC is associated with improved LPRS, CSS and OS, supporting the inclusion of LND during RC for NMIBC, particularly among patients with cTis or cT1 disease. Future prospective studies are warranted to assess the ideal anatomical template of LND in NMIBC.


Asunto(s)
Cistectomía/métodos , Escisión del Ganglio Linfático , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/cirugía , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Estadificación de Neoplasias , Estudios Retrospectivos , Tasa de Supervivencia , Neoplasias de la Vejiga Urinaria/mortalidad
11.
Opt Lett ; 47(2): 261-264, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-35030582

RESUMEN

We present a technique to optimize the intrapulse difference frequency generation efficiency for mid-infrared generation. The approach employs a multi-order wave plate that is designed to selectively rotate the polarization state of the incoming spectral components on the relevant orthogonal axes for subsequent nonlinear interaction. We demonstrate a significant increase of the mid-infrared average power generated, of a factor ≥2.5 compared with the conventional scheme, owing to an optimally distributed number of photons enrolled in the difference frequency generation process.

12.
Opt Lett ; 47(19): 4885-4888, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36181142

RESUMEN

We demonstrate an ultrafast mid-infrared source architecture that implements both intrapulse difference frequency generation (iDFG) and further optical parametric amplification (OPA), in an all-inline configuration. The source is driven by a nonlinearly compressed high-energy Yb-doped-fiber amplifier delivering 7.4 fs pulses at a central wavelength of 1030 nm, at a repetition rate of 250 kHz. It delivers 1 µJ, 73 fs pulses at a central wavelength of 8 µm, tunable over more than one octave. By enrolling all the pump photons in the iDFG process and recycling the long wavelength pump photons amplified in the iDFG in the subsequent OPA, we obtain an unprecedented overall optical efficiency of 2%. These performances, combining high energy and repetition rate in a very simple all-inline setup, make this technique ideally suited for a growing number of applications, such as high harmonic generation in solids or two-dimensional infrared spectroscopy experiments.

14.
Opt Express ; 27(20): 27891-27901, 2019 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-31684550

RESUMEN

We demonstrate coherent beam combining of four high brightness tapered amplifiers in pulsed, quasi continuous wave (QCW) operation, seeded by a 976 nm laser diode. The maximum power of 22.7 W was achieved with > 64% combining efficiency in a close to diffraction limited beam. We discuss turn-on dynamics of tapered amplifiers operated in pulsed mode in detail.

15.
Opt Express ; 27(3): 1958-1967, 2019 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-30732241

RESUMEN

We demonstrate a hybrid dual-stage nonlinear compression scheme, which allows the temporal compression of 330 fs-pulses down to 6.8 fs-pulses, with an overall transmission of 61%. This high transmission is obtained by using a first compression stage based on a gas-filled multipass cell, and a second stage based on a large-core gas-filled capillary. The source output is fully characterized in terms of spectral, temporal, spatial, and short- and long-term stability properties. The system's compactness, stability, and high average power makes it ideally suited to drive high photon flux XUV sources through high harmonic generation.

16.
Opt Express ; 27(8): 11830-11843, 2019 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-31053023

RESUMEN

Luminescent concentrators (LC) enable breaking the limit of geometrical concentration imposed by the brightness theorem. They enable increasing the brightness of Lambertian light sources such as (organic) light-emitting diodes. However, for illumination applications, light emitted in the high-index material needs to be outcoupled to free space, raising important light extraction issues. Supported by an intuitive graphical representation, we propose a simple design for light extraction: a wedged output side facet, breaking the symmetry of the traditional rectangular slab design. Angular emission patterns as well as ray-tracing simulations are reported on Ce:YAG single crystal concentrators cut with different wedge angles, and are compared with devices having flat or roughened exit facets. The wedge output provides a simple and versatile way to simultaneously enhance the extracted power (up to a factor of 2) and the light directivity (radiant intensity increased by up to 2.2.).

17.
Opt Express ; 27(2): 928-937, 2019 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-30696171

RESUMEN

We report on a coherent beam combination of three high-brightness tapered amplifiers, which are seeded by a single-frequency laser at λ = 976 nm in a simple architecture with efficiently cooled emitters. The maximal combined power of 12.9 W is achieved at a combining efficiency of > 65%, which is limited by the amplifiers' intrinsic beam quality. The coherent combination cleans up the spatial profile, as the central lobe's power content increases by up to 86%. This high-brightness infrared beam is converted into the visible by second harmonic generation. This results in a high non-linear conversion efficiency of 4.5%/W and a maximum power over 2 W at 488 nm, which is limited by thermal effects in the periodically poled lithium niobate (PPLN).

18.
Opt Lett ; 44(16): 3909-3912, 2019 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-31415509

RESUMEN

We report on the carrier-envelope phase (CEP) stabilization of a Yb-doped fiber amplifier system delivering 30 µJ pulses at 100 kHz repetition rate. A single-shot, every-shot measurement of the CEP stability based on a simple f-2f interferometer is performed, yielding a CEP standard deviation of 320 mrad rms over 1 s. Long-term stability is also assessed, with 380 mrad measured over 1 h. This level of performance is allowed by a hybrid architecture, including a passively CEP-stabilized front-end based on difference frequency generation and an active CEP stabilization loop for the fiber amplifier system, acting on a telecom-grade integrated LiNbO3 phase modulator. Together with recent demonstrations of temporal compression down to the few-cycle regime, the presented results demonstrate the relevance of the Yb-doped high repetition rate laser for attoscience.

19.
Opt Lett ; 43(10): 2252-2255, 2018 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-29762565

RESUMEN

We demonstrate nonlinear temporal compression of a high-energy Yb-doped fiber laser source in a multipass cell filled with argon. The 160 µJ 275 fs input pulses are compressed down to 135 µJ 33 fs at the output, corresponding to an overall transmission of 85%. We also analyze the output beam, revealing essentially no space-time couplings. We believe this technique can be scalable to higher pulse energies and shorter pulse durations, enabling access to a wider parameter range for a large variety of ultrafast laser sources.

20.
Acta Derm Venereol ; 98(7): 648-654, 2018 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-29405245

RESUMEN

Interleukin 17-antagonist secukinumab demonstrated high efficacy for treatment of psoriasis in randomized controlled trials. However, performance in daily practice may differ from trials. Drug survival is a comprehensive outcome covering effectiveness and safety, suitable for analyses of daily practice. The aim of this study was to evaluate drug survival of secukinumab in a daily practice psoriasis cohort. Data were collected from 13 hospitals. Drug survival was analysed using Kaplan-Meier survival curves, split for reason of discontinuation. In total, 196 patients were included (83% biologic experienced). Overall, 12 and 18 months drug survival of secukinumab was 76% and 67%, respectively, and was mostly determined by ineffectiveness. There was a trend towards shorter drug survival in women and in biologic experienced patients. Thirteen percent of patients experienced at least one episode of fungal infection. This is one of the first studies of drug survival of secukinumab in patients with psoriasis treated in daily practice.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Fármacos Dermatológicos/uso terapéutico , Psoriasis/tratamiento farmacológico , Adulto , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales Humanizados , Fármacos Dermatológicos/efectos adversos , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Países Bajos , Modelos de Riesgos Proporcionales , Psoriasis/diagnóstico , Psoriasis/inmunología , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
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