Project description:Interventions: An observational study at the Dutch Screening for Breast Cancer will be performed in 66 postmenopausal women without breast cancer. By acquiring insight into the intestinal microbiota composition of postmenopausal women without breast cancer, a control group will be set up for already existing research lines in microbiota research in breast cancer patients at MUMC+. Fecal samples and questionnaires will be collected. The intestinal microbiota composition and absolute abundance of the fecal samples will be analyzed by with 16S rRNA Next Generation Sequencing (NGS) with subsequent qPCR to convert relative abundance to absolute abundance.
Primary outcome(s): The primary endpoints include the microbiota composition.
Study Design: N/A , unknown, Other
Project description:RNA-seq analysis of with known quantity of cell numbers and reference RNA (ERCC) to determine absolute abundance of endogenous mRNA abundances in B cells
Project description:<p>Studies have emphasized the importance of disease-associated microorganisms in perturbed communities, however, the protective roles of commensals are largely under recognized and poorly understood. Using acne as a model disease, we investigated the determinants of the overall virulence property of the skin microbiota when disease- and health-associated organisms coexist in the community. By ultra-deep metagenomic shotgun sequencing, we revealed higher relative abundances of propionibacteria and Propionibacterium acnes phage in healthy skin. In acne patients, the microbiome composition at the species level and at P. acnes strain level was more diverse than in healthy individuals, with enriched virulence-associated factors and reduced abundance of metabolic synthesis genes. Based on the abundance profiles of the metagenomic elements, we constructed a quantitative prediction model, which classified the clinical states of the host skin with high accuracy in both our study cohort (85%) and an independent sample set (86%). Our results suggest that the balance between metagenomic elements, not the mere presence of disease-associated strains, shapes the overall virulence property of the skin microbiota. This study provides new insights into the microbial mechanism of acne pathogenesis and suggests probiotic and phage therapies as potential acne treatments to modulate the skin microbiota and to maintain skin health.</p>
Project description:This is a use case to show that, given any automatic metagenomic classification model for the documents, we can convert those to ONNX (Open Neural Network Exchange) format; it also consists of the Dockerfile that can be used to prepare a docker image. This conversion ensures interoperability and open access. The ONNX format utility can perform the following essential tasks: model conversion, inference, inspection, and optimization. Reference: 1) https://github.com/elixir-europe/biohackathon-projects-2022/tree/main/9 2) https://www.ebi.ac.uk/biomodels/search?query=Maaly+Nassar&domain=biomodels 3) https://gitlab.com/maaly7/emerald_metagenomics_annotations 4) This model is built upon the model of the following publication: Maaly Nassar, Alexander B Rogers, Francesco Talo', Santiago Sanchez, Zunaira Shafique, Robert D Finn, Johanna McEntyre, A machine learning framework for discovery and enrichment of metagenomics metadata from open access publications, GigaScience, Volume 11, 2022, giac077, https://doi.org/10.1093/gigascience/giac077
Project description:Although identification of single gene mutations associated with SRNS have yielded insights into pathogenic mechanisms and localized its pathogenesis to glomerular podocytes, the disease mechanisms of SRNS remain obscure. ADCK4 mutations usually manifest as steroid-resistant nephrotic syndrome, and cause coenzyme Q10 (CoQ10) deficiency.The reduced form of CoQ (QH2) plays a role as a potent lipid-soluble antioxidant, scavenging free radicals and preventing lipid peroxidative damage. Although ADCK4 KO in itself did not affect the viability of cultured podocytes, we examined cell viability upon arachidonic acid (AA) treatment because CoQ-deficient yeast mutants were found to be more sensitive to polyunsaturated fatty acids such as AA, which are prone to autoxidation and breakdown into toxic products. To comprehensively understand the molecular changes induced by the KO of ADCK4, we performed proteomic analysis and quantified protein abundance changes by MS-based proteomics using isobaric tag for relative and absolute quantification (iTRAQ) in podocytes with and without AA treatment.
Project description:Absolute quantification of proteome is one of the most important tasks in proteomic research. The aim in this analysis is selection of reference tryptic peptides used for stable isotope-labeled standard, based on their spectral peak intensities. Approximate abundance is also calculated by label-free quantitative method, in which identification frequency (counts of peptide spectral matchings) in each protein is normalized by observability of peptide ions to calculate relative copy number of proteins. For proteins with higher relative copy number, peptide ions that fulfill following criteria — 2- or 3-charge state, without methionine residues and well known post-translational modification sites — are selected as reference tryptic peptides.
Project description:The fraction of dissolved dimethylsulfoniopropionate (DMSPd) converted by marine bacterioplankton into the climate-active gas dimethylsulfide (DMS) varies widely in the ocean, with the factors that determine this value still largely unknown. One current hypothesis is that the ratio of DMS formation:DMSP demethylation is determined by DMSP availability, with 'availability' in both an absolute sense (i.e., concentration in seawater) and in a relative sense (i.e., proportionally to other labile organic S compounds) being proposed as the critical factor. We investigated these models during an experimentally-induced phytoplankton bloom using an environmental microarray targeting DMSP-related gene expression in the Roseobacter group, a taxon of marine bacteria known to play an important role in the surface ocean sulfur cycle. The array consisted of 1,578 probes to 431 genes, including those previously linked to DMSP degradation as well as core genes common in sequenced Roseobacter genomes. The prevailing pattern of Roseobacter gene expression showed depletion of DMSP-related transcripts during the peak of the bloom, despite the fact that absolute concentrations and flux of DMSP-related compounds were increasing. A likely interpretation is that DMSPd was assimilated by Roseobacter populations in proportion to its relative abundance in the organic matter pool (the “relative sense” hypothesis), and that it is not taken up in preference to other sources of labile organic sulfur or carbon produced during the bloom. The relative investment of the Roseobacter community in DMSP demethylation did not predict the fractional conversion of DMSP to DMS, however, suggesting a complex regulatory process that may involve multiple fates of DMSPd.
Project description:Rheumatoid arthritis (RA) is a systemic autoimmune and inflammatory disease. Plasma biomarkers are critical for understanding disease mechanisms, treatment effects, and diagnosis. Mass spectrometry-based proteomics is a powerful tool for unbiased biomarker discovery. However, plasma proteomics is significantly hampered by signal interference from high-abundance proteins, low overall protein coverage, and high levels of missing data from data-dependent acquisition (DDA). To achieve quantitative proteomic analysis for plasma samples with a balance of throughput, performance, and cost, we developed a workflow incorporating plate-based high abundance protein depletion and sample preparation, comprehensive peptide spectral library building, and data-independent acquisition (DIA) SWATH mass spectrometry-based methodology. In this study, we analyzed plasma samples from both RA patients and healthy donors. The results showed that the new workflow performance exceeded that of the current state-of-the-art depletion-based plasma proteomic platforms in terms of both data quality and proteome coverage. Proteins from biological processes related to the activation of systemic inflammation, suppression of platelet function, and loss of muscle mass were enriched and differentially expressed in RA. Some plasma proteins, particularly acute phase reactant proteins, showed great power to distinguish between RA patients and healthy donors. Moreover, protein isoforms in the plasma were also analyzed, providing even deeper proteome coverage. This workflow can serve as a basis for further application in discovering plasma biomarkers of other diseases.
Project description:Reprogramming intermediates (pre-iPSCs) were subjected to control DMSO, ascorbic acid (AA), 2i ( MAP kinase inhibitor + GSKinhibitor) or AA+2i conditions to assess conversion to the iinduced pluripotent stem cell state (iPSC) after 10days.