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131.
Maddalena Cagnone Roberta Salvini Anna Bardoni Marco Fumagalli Paolo Iadarola Simona Viglio 《Electrophoresis》2019,40(1):151-164
Detection of proteins which may be potential biomarkers of disorders represents a big step forward in understanding the molecular mechanisms that underlie pathological processes. In this context proteomics plays the important role of opening a path for the identification of molecular signatures that can potentially assist in early diagnosis of several clinical disturbances. Aim of this report is to provide an overview of the wide variety of proteomic strategies that have been applied to the investigation of chronic obstructive pulmonary disease (COPD), a severe disorder that causes an irreversible damage to the lungs and for which there is no cure yet. The results in this area published over the past decade show that proteomics indeed has the ability of monitoring alterations in expression profiles of proteins from fluids/tissues of patients affected by COPD and healthy controls. However, these data also suggest that proteomics, while being an attractive tool for the identification of novel pathological mediators of COPD, remains a technique mainly generated and developed in research laboratories. Great efforts dedicated to the validation of these biological signatures will result in the proof of their clinical utility. 相似文献
132.
G. Principi A. Gupta R. Gupta C. Tosello L. M. Gratton A. Maddalena S. Lo Russo 《Hyperfine Interactions》1992,69(1-4):627-630
Solid state reaction in Fe?Si multilayers occuring at 300°C and 385°C has been studied using Mössbauer spectroscopy and RBS measurements. Annealing at 300°C results in partial amorphization of the system, while annealing at 385°C results in formation of crystalline phases. Possible mechanism for amorphization has been discussed. 相似文献
133.
Weighardt F Barbati C Paoletti C Querci M Kay S De Beuckeleer M Van den Eede G 《Journal of AOAC International》2004,87(6):1342-1355
In Europe, a growing interest for reliable techniques for the quantification of genetically modified component(s) of food matrixes is arising from the need to comply with the European legislative framework on novel food products. Real-time polymerase chain reaction (PCR) is currently the most powerful technique for the quantification of specific nucleic acid sequences. Several real-time PCR methodologies based on different molecular principles have been developed for this purpose. The most frequently used approach in the field of genetically modified organism (GMO) quantification in food or feed samples is based on the 5'-3'-exonuclease activity of Taq DNA polymerase on specific degradation probes (TaqMan principle). A novel approach was developed for the establishment of a TaqMan quantification system assessing GMO contents around the 1% threshold stipulated under European Union (EU) legislation for the labeling of food products. The Zea mays T25 elite event was chosen as a model for the development of the novel GMO quantification approach. The most innovative aspect of the system is represented by the use of sequences cloned in plasmids as reference standards. In the field of GMO quantification, plasmids are an easy to use, cheap, and reliable alternative to Certified Reference Materials (CRMs), which are only available for a few of the GMOs authorized in Europe, have a relatively high production cost, and require further processing to be suitable for analysis. Strengths and weaknesses of the use of novel plasmid-based standards are addressed in detail. In addition, the quantification system was designed to avoid the use of a reference gene (e.g., a single copy, species-specific gene) as normalizer, i.e., to perform a GMO quantification based on an absolute instead of a relative measurement. In fact, experimental evidences show that the use of reference genes adds variability to the measurement system because a second independent real-time PCR-based measurement must be performed. Moreover, for some reference genes no sufficient information on copy number in and among genomes of different lines is available, making adequate quantification difficult. Once developed, the method was subsequently validated according to IUPAC and ISO 5725 guidelines. Thirteen laboratories from 8 EU countries participated in the trial. Eleven laboratories provided results complying with the predefined study requirements. Repeatability (RSDr) values ranged from 8.7 to 15.9%, with a mean value of 12%. Reproducibility (RSDR) values ranged from 16.3 to 25.5%, with a mean value of 21%. Following Codex Alimentarius Committee guidelines, both the limits of detection and quantitation were determined to be <0.1%. 相似文献
134.
Maddalena Bonanzinga Filippo Cammaroto Bruno A. Pansera 《Central European Journal of Mathematics》2011,9(3):583-592
The definition of monotone weak Lindelöfness is similar to monotone versions of other covering properties: X is monotonically weakly Lindelöf if there is an operator r that assigns to every open cover U a family of open sets r(U) so that (1) ∪r(U) is dense in X, (2) r(U) refines U, and (3) r(U) refines r(V) whenever U refines V. Some examples and counterexamples of monotonically weakly Lindelöf spaces are given and some basic properties such as the behavior with respect to products and subspaces are discussed. 相似文献
135.
Aggarwal VK Binanzer M de Ceglie MC Gallanti M Glasspoole BW Kendrick SJ Sonawane RP Vázquez-Romero A Webster MP 《Organic letters》2011,13(6):1490-1493
Tertiary allyl- or crotylsilanes have been prepared in high er and dr via the lithiation-borylation reaction of alkyl carbamates with silaboronates. Using a related strategy, quaternary allylsilanes could be accessed in similarly high er. 相似文献
136.
Lorella Paparo Maria Antonia Maglio Maddalena Cortese Cristina Bruno Mario Capasso Erika Punzo Veronica Ferrucci Vito Alessandro Lasorsa Maurizio Viscardi Giovanna Fusco Pellegrino Cerino Alessia Romano Riccardo Troncone Massimo Zollo 《Molecules (Basel, Switzerland)》2022,27(3)
Butyrate is a major gut microbiome metabolite that regulates several defense mechanisms against infectious diseases. Alterations in the gut microbiome, leading to reduced butyrate production, have been reported in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. A new butyrate releaser, useful for all the known applications of butyrate, presenting physiochemical characteristics suitable for easy oral administration, (N-(1-carbamoyl-2-phenyl-ethyl) butyramide (FBA), has been recently developed. We investigated the protective action of FBA against SARS-CoV-2 infection in the human small intestine and enterocytes. Relevant aspects of SARS-CoV-2 infection were assessed: infectivity, host functional receptor angiotensin-converting enzyme-2 (ACE2), transmembrane protease serine 2 (TMPRSS2), neuropilin-1 (NRP1), pro-inflammatory cytokines expression, genes involved in the antiviral response and the activation of Nf-kB nuclear factor (erythroid-derived 2-like) 2 (Nfr2) pathways. We found that FBA positively modulates the crucial aspects of the infection in small intestinal biopsies and human enterocytes, reducing the expression of ACE2, TMPRSS2 and NRP1, pro-inflammatory cytokines interleukin (IL)-15, monocyte chemoattractant protein-1 (MCP-1) and TNF-α, and regulating several genes involved in antiviral pathways. FBA was also able to reduce the number of SARS-CoV-2-infected cells, and ACE2, TMPRSS2 and NRP1 expression. Lastly, through the inhibition of Nf-kB and the up-regulation of Nfr2, it was also able to reduce the expression of pro-inflammatory cytokines IL-15, MCP-1 and TNF-α in human enterocytes. The new butyrate releaser, FBA, exerts a preventive action against SARS-CoV-2 infection. It could be considered as an innovative strategy to limit COVID-19. 相似文献