Project description:The short length of miRNAs results in a high dynamic range of melting temperatures and therefore impedes a proper selection of detection probes or optimized PCR primers. While miRNA microarrays allow for massive parallel and accurate relative measurement of all known miRNAs, they have so far been less useful as an assay for absolute quantification. Here we developed a new method based not only to the hybridization process that presents the limits before described, but integrating the hybridization to an enzymatic reaction. Moreover we introduced spike-in in the hybridization-enzymatic reaction allowing the quantification of miRNAs respect to them, canceling biases related to sequence, labeling, or hybridization. An alternative method for the absolute miRNA quantization was recently proposed by Bissels (Absolute quantification of microRNAs by using a universal reference. RNA). It was based on the Absolute quantification of microRNAs by using a universal reference consisting of 954 synthetic human, mouse, rat, and viral miRNAs, with each individual oligoribonucleotide present in equimolar concentrations with tested miRNAs. Thereby, any single miRNA detected on a microarray can be quantified by directly comparing its signal intensity with the one obtained by the same miRNA sequence present in the universal reference adjusting for biases related to sequence, labeling, hybridization, or signal detection. Our method allowed the detection of a comparable concentration of miRNA (10-18 moles to 10-14 moles in a linear range) (see Figure), but allows controlling the hybridization quality and reproducibility basing on the results of the interpolation of the spike-in dependent curve. Moreover, our method does not influenced by phenomena imputable to different labeling process due to different sequences because labeling was due only to the incorporation of biotin-d(A) if the hybridized miRNA acted as primer for the klenow enzyme. This method allowed the discussion of miRNA genes expression in 14 different tissues relating it with tissue anatomical proximity and functional similarity.

Project description:The short length of miRNAs results in a high dynamic range of melting temperatures and therefore impedes a proper selection of detection probes or optimized PCR primers. While miRNA microarrays allow for massive parallel and accurate relative measurement of all known miRNAs, they have so far been less useful as an assay for absolute quantification. Here we developed a new method based not only to the hybridization process that presents the limits before described, but integrating the hybridization to an enzymatic reaction. Moreover we introduced spike-in in the hybridization-enzymatic reaction allowing the quantification of miRNAs respect to them, canceling biases related to sequence, labeling, or hybridization. An alternative method for the absolute miRNA quantization was recently proposed by Bissels (Absolute quantification of microRNAs by using a universal reference. RNA). It was based on the Absolute quantification of microRNAs by using a universal reference consisting of 954 synthetic human, mouse, rat, and viral miRNAs, with each individual oligoribonucleotide present in equimolar concentrations with tested miRNAs. Thereby, any single miRNA detected on a microarray can be quantified by directly comparing its signal intensity with the one obtained by the same miRNA sequence present in the universal reference adjusting for biases related to sequence, labeling, hybridization, or signal detection. Our method allowed the detection of a comparable concentration of miRNA (10^-18 moles to 10^-14 moles in a linear range), but allows controlling the hybridization quality and reproducibility basing on the results of the interpolation of the spike-in dependent curve. Moreover, our method does not influenced by phenomena imputable to different labeling process due to different sequences because labeling was due only to the incorporation of biotin-d(A) if the hybridized miRNA acted as primer for the klenow enzyme. This method allowed the discussion of miRNA genes expression in 9 different tissues relating them with tissue functionality in the cardiocirculatory system.

Project description:Purpose: The goals of this study is to determine the best method of gene expression quantification (RNA-seq, Microarray, NanoString) and amplification kits adapted to low-input and/or low-quality RNA samples (FFPE samples) Methods: Mouse bladder cancer cell line (mouse bladder cancer cell line, BC57) and mouse normal mouse normal urothelium were fixed in formalin and embedded in paraffin (FFPE), andfesh frozen (FF) in liquid nitrogen. The total RNA of these 4 samples were tested by 3 technologies (NanoString, RNA-seq and Microarray) and the results were compared to its reference (high-quality and high-input RNA of mouse bladder cancer cell line and mouse normal mouse normal urothelium). For NanoString with low-input RNA samples, each sample was tested by NanoString quantification after amplification by SMARTer Stranded Total RNA-Seq Kit - Pico Input mammelian and Ovation SoLo NuGEN RNA-seq System, and NanoString based on PCR approach with three input quantities: 50pg, 250pg and 2ng of total RNA, except for NanoString quantification after amplification by SMARTer Stranded Total RNA-Seq Kit - Pico Input mammelian kit for which the minimum recommended quantity was 250pg of total RNA. NanoString direct quantification was also done for FF and FFPE samples at high amount (50ng of total RNA) and results obtained from FF samples were considered as the reference. To determine which is the method for NanoString technology, low-input and low-quality RNA samples, we performed NanoString control quality metrics, principal component analysis, and a differential analysis between the mouse bladder cancer cell lines and the mouse normal mouse normal urothelium for each input quantity, amplification method and method of sample preservation (FF or FFPE). Results: The NanoString based PCR based approach is recommended for quantification of gene expression of FFPE and FF samples from 250pg of total RNA. However, NanoString quantification after amplification by SMARTer Stranded Total RNA-Seq Kit - Pico Input mammelian and Ovation SoLo NuGEN RNA-seq System is not recommended for FF and FFPE from low-input samples.

Project description:The short length of miRNAs results in a high dynamic range of melting temperatures and therefore impedes a proper selection of detection probes or optimized PCR primers. While miRNA microarrays allow for massive parallel and accurate relative measurement of all known miRNAs, they have so far been less useful as an assay for absolute quantification. Here we developed a new method based not only to the hybridization process that presents the limits before described, but integrating the hybridization to an enzymatic reaction. Moreover we introduced spike-in in the hybridization-enzymatic reaction allowing the quantification of miRNAs respect to them, canceling biases related to sequence, labeling, or hybridization. An alternative method for the absolute miRNA quantization was recently proposed by Bissels (Absolute quantification of microRNAs by using a universal reference. RNA). It was based on the Absolute quantification of microRNAs by using a universal reference consisting of 954 synthetic human, mouse, rat, and viral miRNAs, with each individual oligoribonucleotide present in equimolar concentrations with tested miRNAs. Thereby, any single miRNA detected on a microarray can be quantified by directly comparing its signal intensity with the one obtained by the same miRNA sequence present in the universal reference adjusting for biases related to sequence, labeling, hybridization, or signal detection. Our method allowed the detection of a comparable concentration of miRNA (10-18 moles to 10-14 moles in a linear range) (see Figure), but allows controlling the hybridization quality and reproducibility basing on the results of the interpolation of the spike-in dependent curve. Moreover, our method does not influenced by phenomena imputable to different labeling process due to different sequences because labeling was due only to the incorporation of biotin-d(A) if the hybridized miRNA acted as primer for the klenow enzyme. This method allowed the discussion of miRNA genes expression in 14 different tissues relating it with tissue anatomical proximity and functional similarity. 2K microarray was hybridized with small RNAs from 14 different tissues (Atrium Sinister; Skin; Liver; W_B_A: White Blood Cells from Arteriosum blood; W_B_V: White Blood Cells from Venosum blood; Lymph Node; Tongue; Spleen; Skeletal Muscle; Lung; Kidney; Stomach; Adipose Tissue; Ventricle Sinister). Each experiment was replicated to have 28 experiments and miRNA gene expression was correlated with mRNA gene expression in the same samples.

			Action	DRS
	a_MTBLS13986_LC-MS_alternating_hilic_metabolite_profiling.txt	Txt
	i_Investigation.txt	Txt
	m_MTBLS13986_LC-MS_alternating_hilic_metabolite_profiling_v2_maf.tsv	Tabular
	s_MTBLS13986.txt	Txt

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Rapid and targeted HILIC-MS/MS quantification of urinary metabolites reveals metabolic alterations in COVID-19 patients

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