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Dimuccio V, Bellucci L, Genta M, Grange C, Brizzi MF, Gili M, Gallo S, Centomo ML, Collino F, Bussolati B. Upregulation of miR145 and miR126 in EVs from Renal Cells Undergoing EMT and Urine of Diabetic Nephropathy Patients. Int J Mol Sci 2022; 23:12098. [PMID: 36292960 PMCID: PMC9603196 DOI: 10.3390/ijms232012098] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 10/03/2022] [Accepted: 10/06/2022] [Indexed: 08/30/2023] Open
Abstract
Diabetic nephropathy (DN) is a severe kidney-related complication of type 1 and type 2 diabetes and the most frequent cause of end-stage kidney disease. Extracellular vesicles (EVs) present in the urine mainly derive from the cells of the nephron, thus representing an interesting tool mirroring the kidney's physiological state. In search of the biomarkers of disease progression, we here assessed a panel of urinary EV miRNAs previously related to DN in type 2 diabetic patients stratified based on proteinuria levels. We found that during DN progression, miR145 and miR126 specifically increased in urinary EVs from diabetic patients together with albuminuria. In vitro, miRNA modulation was assessed in a model of TGF-β1-induced glomerular damage within a three-dimensional perfusion system, as well as in a model of tubular damage induced by albumin and glucose overload. Both renal tubular cells and podocytes undergoing epithelial to mesenchymal transition released EVs containing increased miR145 and miR126 levels. At the same time, miR126 levels were reduced in EVs released by glomerular endothelial cells. This work highlights a modulation of miR126 and miR145 during the progression of kidney damage in diabetes as biomarkers of epithelial to mesenchymal transition.
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Affiliation(s)
- Veronica Dimuccio
- Department of Molecular Biotechnology and Health Sciences, University of Turin, 10124 Turin, Italy
| | - Linda Bellucci
- Laboratory of Translational Research in Paediatric Nephro-Urology, Fondazione Ca’ Granda IRCCS Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Marianna Genta
- Department of Molecular Biotechnology and Health Sciences, University of Turin, 10124 Turin, Italy
| | - Cristina Grange
- Department of Medical Sciences, University of Turin, 10124 Turin, Italy
| | | | - Maddalena Gili
- Department of Medical Sciences, University of Turin, 10124 Turin, Italy
| | - Sara Gallo
- Department of Medical Sciences, University of Turin, 10124 Turin, Italy
| | - Maria Laura Centomo
- Department of Molecular Biotechnology and Health Sciences, University of Turin, 10124 Turin, Italy
| | - Federica Collino
- Laboratory of Translational Research in Paediatric Nephro-Urology, Fondazione Ca’ Granda IRCCS Ospedale Maggiore Policlinico, 20122 Milan, Italy
- Department of Clinical Sciences and Community Health, University of Milan, 20122 Milan, Italy
| | - Benedetta Bussolati
- Department of Molecular Biotechnology and Health Sciences, University of Turin, 10124 Turin, Italy
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Ekulu PM, Adebayo OC, Decuypere JP, Bellucci L, Elmonem MA, Nkoy AB, Mekahli D, Bussolati B, van den Heuvel LP, Arcolino FO, Levtchenko EN. Novel Human Podocyte Cell Model Carrying G2/G2 APOL1 High-Risk Genotype. Cells 2021; 10:cells10081914. [PMID: 34440683 PMCID: PMC8391400 DOI: 10.3390/cells10081914] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 07/20/2021] [Accepted: 07/23/2021] [Indexed: 02/01/2023] Open
Abstract
Apolipoprotein L1 (APOL1) high-risk genotypes (HRG), G1 and G2, increase the risk of various non-diabetic kidney diseases in the African population. To date, the precise mechanisms by which APOL1 risk variants induce injury on podocytes and other kidney cells remain unclear. Trying to unravel these mechanisms, most studies have used animal or cell models created by gene editing. We developed and characterised conditionally immortalised human podocyte cell lines derived from urine of a donor carrying APOL1 HRG G2/G2. Following induction of APOL1 expression by polyinosinic-polycytidylic acid (poly(I:C)), we assessed functional features of APOL1-induced podocyte dysfunction. As control, APOL1 wild type (G0/G0) podocyte cell line previously generated from a Caucasian donor was used. Upon exposure to poly(I:C), G2/G2 and G0/G0 podocytes upregulated APOL1 expression resulting in podocytes detachment, decreased cells viability and increased apoptosis rate in a genotype-independent manner. Nevertheless, G2/G2 podocyte cell lines exhibited altered features, including upregulation of CD2AP, alteration of cytoskeleton, reduction of autophagic flux and increased permeability in an in vitro model under continuous perfusion. The human APOL1 G2/G2 podocyte cell model is a useful tool for unravelling the mechanisms of APOL1-induced podocyte injury and the cellular functions of APOL1.
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Affiliation(s)
- Pepe M. Ekulu
- Department of Development and Regeneration, Katholieke Universiteit Leuven, 3000 Leuven, Belgium; (P.M.E.); (O.C.A.); (J.-P.D.); (A.B.N.); (D.M.); (L.P.v.d.H.); (E.N.L.)
- Department of Paediatrics, Division of Nephrology, Faculty of Medicine, University Hospital of Kinshasa, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Oyindamola C. Adebayo
- Department of Development and Regeneration, Katholieke Universiteit Leuven, 3000 Leuven, Belgium; (P.M.E.); (O.C.A.); (J.-P.D.); (A.B.N.); (D.M.); (L.P.v.d.H.); (E.N.L.)
- Centre for Molecular and Vascular Biology, Department of Cardiovascular Sciences, Katholieke Universiteit Leuven, 3000 Leuven, Belgium
| | - Jean-Paul Decuypere
- Department of Development and Regeneration, Katholieke Universiteit Leuven, 3000 Leuven, Belgium; (P.M.E.); (O.C.A.); (J.-P.D.); (A.B.N.); (D.M.); (L.P.v.d.H.); (E.N.L.)
| | - Linda Bellucci
- Department of Molecular Biotechnology and Health Sciences, University of Turin, 10124 Turin, Italy; (L.B.); (B.B.)
| | - Mohamed A. Elmonem
- Department of Clinical and Chemical Pathology, Faculty of Medicine, Cairo University, Cairo 11628, Egypt;
| | - Agathe B. Nkoy
- Department of Development and Regeneration, Katholieke Universiteit Leuven, 3000 Leuven, Belgium; (P.M.E.); (O.C.A.); (J.-P.D.); (A.B.N.); (D.M.); (L.P.v.d.H.); (E.N.L.)
- Department of Paediatrics, Division of Nephrology, Faculty of Medicine, University Hospital of Kinshasa, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Djalila Mekahli
- Department of Development and Regeneration, Katholieke Universiteit Leuven, 3000 Leuven, Belgium; (P.M.E.); (O.C.A.); (J.-P.D.); (A.B.N.); (D.M.); (L.P.v.d.H.); (E.N.L.)
- Department of Paediatrics, Division of Nephrology, University Hospitals Leuven, 3000 Leuven, Belgium
| | - Benedetta Bussolati
- Department of Molecular Biotechnology and Health Sciences, University of Turin, 10124 Turin, Italy; (L.B.); (B.B.)
| | - Lambertus P. van den Heuvel
- Department of Development and Regeneration, Katholieke Universiteit Leuven, 3000 Leuven, Belgium; (P.M.E.); (O.C.A.); (J.-P.D.); (A.B.N.); (D.M.); (L.P.v.d.H.); (E.N.L.)
- Department of Paediatric Nephrology, Radboud University Medical Centre, 6500 Nijmegen, The Netherlands
| | - Fanny O. Arcolino
- Department of Development and Regeneration, Katholieke Universiteit Leuven, 3000 Leuven, Belgium; (P.M.E.); (O.C.A.); (J.-P.D.); (A.B.N.); (D.M.); (L.P.v.d.H.); (E.N.L.)
- Correspondence: ; Tel.: +32-16372647
| | - Elena N. Levtchenko
- Department of Development and Regeneration, Katholieke Universiteit Leuven, 3000 Leuven, Belgium; (P.M.E.); (O.C.A.); (J.-P.D.); (A.B.N.); (D.M.); (L.P.v.d.H.); (E.N.L.)
- Department of Paediatrics, Division of Nephrology, University Hospitals Leuven, 3000 Leuven, Belgium
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3
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Bellucci L, Montini G, Collino F, Bussolati B. Mesenchymal Stromal Cell-Derived Extracellular Vesicles Pass through the Filtration Barrier and Protect Podocytes in a 3D Glomerular Model under Continuous Perfusion. Tissue Eng Regen Med 2021; 18:549-560. [PMID: 34313970 PMCID: PMC8325748 DOI: 10.1007/s13770-021-00374-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 06/30/2021] [Accepted: 07/07/2021] [Indexed: 12/20/2022] Open
Abstract
Background: Dynamic cultures, characterized by continuous fluid reperfusion, elicit physiological responses from cultured cells. Mesenchymal stem cell-derived EVs (MSC-EVs) has been proposed as a novel approach in treating several renal diseases, including acute glomerular damage, by using traditional two-dimensional cell cultures and in vivo models. We here aimed to use a fluidic three-dimensional (3D) glomerular model to study the EV dynamics within the glomerular structure under perfusion. Methods: To this end, we set up a 3D glomerular model culturing human glomerular endothelial cells and podocytes inside a bioreactor on the opposite sides of a porous membrane coated with type IV collagen. The bioreactor was connected to a circuit that allowed fluid passage at the rate of 80 µl/min. To mimic glomerular damage, the system was subjected to doxorubicin administration in the presence of therapeutic MSC-EVs. Results: The integrity of the glomerular basal membrane in the 3D glomerulus was assessed by a permeability assay, demonstrating that the co-culture could limit the passage of albumin through the filtration barrier. In dynamic conditions, serum EVs engineered with cel-miR-39 passed through the glomerular barrier and transferred the exogenous microRNA to podocyte cell lines. Doxorubicin treatment increased podocyte apoptosis, whereas MSC-EV within the endothelial circuit protected podocytes from damage, decreasing cell death and albumin permeability. Conclusion: Using an innovative millifluidic model, able to mimic the human glomerular barrier, we were able to trace the EV passage and therapeutic effect in dynamic conditions.
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Affiliation(s)
- Linda Bellucci
- Department of Molecular Biotechnology and Health Sciences, University of Torino, via Nizza 52, 10126, Turin, Italy.,Laboratory of Translational Research in Paediatric Nephro-Urology, Fondazione Ca' Granda IRCCS Ospedale Maggiore Policlinico, Milan, Italy
| | - Giovanni Montini
- Laboratory of Translational Research in Paediatric Nephro-Urology, Fondazione Ca' Granda IRCCS Ospedale Maggiore Policlinico, Milan, Italy.,Department of Clinical Sciences and Community Health, University of Milano, Milan, Italy.,Pediatric Nephrology, Dialysis and Transplant Unit, Fondazione Ca' Granda IRCCS, Policlinico Di Milano, Milan, Italy
| | - Federica Collino
- Laboratory of Translational Research in Paediatric Nephro-Urology, Fondazione Ca' Granda IRCCS Ospedale Maggiore Policlinico, Milan, Italy.,Department of Clinical Sciences and Community Health, University of Milano, Milan, Italy
| | - Benedetta Bussolati
- Department of Molecular Biotechnology and Health Sciences, University of Torino, via Nizza 52, 10126, Turin, Italy.
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4
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Iampietro C, Bellucci L, Arcolino FO, Arigoni M, Alessandri L, Gomez Y, Papadimitriou E, Calogero RA, Cocchi E, Van Den Heuvel L, Levtchenko E, Bussolati B. Molecular and functional characterization of urine-derived podocytes from patients with Alport syndrome. J Pathol 2021; 252:88-100. [PMID: 32652570 PMCID: PMC7589231 DOI: 10.1002/path.5496] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 05/25/2020] [Accepted: 06/22/2020] [Indexed: 12/12/2022]
Abstract
Alport syndrome (AS) is a genetic disorder involving mutations in the genes encoding collagen IV α3, α4 or α5 chains, resulting in the impairment of glomerular basement membrane. Podocytes are responsible for production and correct assembly of collagen IV isoforms; however, data on the phenotypic characteristics of human AS podocytes and their functional alterations are currently limited. The evident loss of viable podocytes into the urine of patients with active glomerular disease enables their isolation in a non‐invasive way. Here we isolated, immortalized, and subcloned podocytes from the urine of three different AS patients for molecular and functional characterization. AS podocytes expressed a typical podocyte signature and showed a collagen IV profile reflecting each patient's mutation. Furthermore, RNA‐sequencing analysis revealed 348 genes differentially expressed in AS podocytes compared with control podocytes. Gene Ontology analysis underlined the enrichment in genes involved in cell motility, adhesion, survival, and angiogenesis. In parallel, AS podocytes displayed reduced motility. Finally, a functional permeability assay, using a podocyte–glomerular endothelial cell co‐culture system, was established and AS podocyte co‐cultures showed a significantly higher permeability of albumin compared to control podocyte co‐cultures, in both static and dynamic conditions under continuous perfusion. In conclusion, our data provide a molecular characterization of immortalized AS podocytes, highlighting alterations in several biological processes related to extracellular matrix remodelling. Moreover, we have established an in vitro model to reproduce the altered podocyte permeability observed in patients with AS. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland..
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Affiliation(s)
- Corinne Iampietro
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Linda Bellucci
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Fanny O Arcolino
- Laboratory of Pediatric Nephrology, Department of Development & Regeneration, University of Leuven, Leuven, Belgium
| | - Maddalena Arigoni
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Luca Alessandri
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Yonathan Gomez
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Elli Papadimitriou
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Raffaele A Calogero
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Enrico Cocchi
- Department of Pediatric Nephrology, University of Torino, Torino, Italy.,Division of Nephrology and Center for Precision Medicine and Genomics, Department of Medicine, Columbia University, New York, NY, USA
| | - Lambertus Van Den Heuvel
- Laboratory of Pediatric Nephrology, Department of Development & Regeneration, University of Leuven, Leuven, Belgium
| | - Elena Levtchenko
- Laboratory of Pediatric Nephrology, Department of Development & Regeneration, University of Leuven, Leuven, Belgium.,Department of Pediatric Nephrology, University Hospitals Leuven, Leuven, Belgium
| | - Benedetta Bussolati
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
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5
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Portone A, Bellucci L, Convertino D, Mezzadri F, Piccinini G, Giambra MA, Miseikis V, Rossi F, Coletti C, Fabbri F. Deterministic synthesis of Cu 9S 5 flakes assisted by single-layer graphene arrays. Nanoscale Adv 2021; 3:1352-1361. [PMID: 36132865 PMCID: PMC9419617 DOI: 10.1039/d0na00997k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 02/01/2021] [Indexed: 06/15/2023]
Abstract
The employment of two-dimensional materials, as growth substrates or buffer layers, enables the epitaxial growth of layered materials with different crystalline symmetries with a preferential crystalline orientation and the synthesis of heterostructures with a large lattice constant mismatch. In this work, we employ single crystalline graphene to modify the sulfurization dynamics of copper foil for the deterministic synthesis of large-area Cu9S5 crystals. Molecular dynamics simulations using the Reax force-field are used to mimic the sulfurization process of a series of different atomistic systems specifically built to understand the role of graphene during the sulphur atom attack over the Cu(111) surface. Cu9S5 flakes show a flat morphology with an average lateral size of hundreds of micrometers. Cu9S5 presents a direct band-gap of 2.5 eV evaluated with light absorption and light emission spectroscopies. Electrical characterization shows that the Cu9S5 crystals present high p-type doping with a hole mobility of 2 cm2 V-1 s-1.
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Affiliation(s)
- A Portone
- NEST, Istituto Nanoscienze - CNR, Scuola Normale Superiore Piazza San Silvestro 12 56127 Pisa Italy
| | - L Bellucci
- NEST, Istituto Nanoscienze - CNR, Scuola Normale Superiore Piazza San Silvestro 12 56127 Pisa Italy
| | - D Convertino
- CNI@NEST, Istituto Italiano di Tecnologia Piazza San Silvestro 12 56127 Pisa Italy
- Graphene Labs, Istituto Italiano di Tecnologia Via Morego 30 16163 Genova Italy
| | - F Mezzadri
- IMEM-CNR Parco Area delle Scienze 37/a Parma 43124 Italy
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma Parco Area delle Scienze 11/A 43124 Parma Italy
| | - G Piccinini
- CNI@NEST, Istituto Italiano di Tecnologia Piazza San Silvestro 12 56127 Pisa Italy
- Scuola Normale Superiore Piazza San Silvestro 12 56127 Pisa Italy
| | - M A Giambra
- CNIT, Sant'Anna Via G. Moruzzi 1 Pisa 56124 Italy
| | - V Miseikis
- CNI@NEST, Istituto Italiano di Tecnologia Piazza San Silvestro 12 56127 Pisa Italy
- Graphene Labs, Istituto Italiano di Tecnologia Via Morego 30 16163 Genova Italy
| | - F Rossi
- IMEM-CNR Parco Area delle Scienze 37/a Parma 43124 Italy
| | - C Coletti
- CNI@NEST, Istituto Italiano di Tecnologia Piazza San Silvestro 12 56127 Pisa Italy
- Graphene Labs, Istituto Italiano di Tecnologia Via Morego 30 16163 Genova Italy
| | - F Fabbri
- NEST, Istituto Nanoscienze - CNR, Scuola Normale Superiore Piazza San Silvestro 12 56127 Pisa Italy
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Bellucci L, Brancolini G, Calzolari A, Carrillo Parramon O, Corni S, Di Felice R. Proteins and Peptides at Gold Surfaces: Insights from Atomistic Simulations. ACTA ACUST UNITED AC 2012. [DOI: 10.1021/bk-2012-1120.ch010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
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Dalvai M, Bellucci L, Fleury L, Lavigne AC, Moutahir F, Bystricky K. H2A.Z-dependent crosstalk between enhancer and promoter regulates cyclin D1 expression. Oncogene 2012; 32:4243-51. [PMID: 23108396 DOI: 10.1038/onc.2012.442] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Revised: 08/09/2012] [Accepted: 08/10/2012] [Indexed: 02/08/2023]
Abstract
H2A.Z association with specific genomic loci is thought to contribute to a chromatin structure that promotes transcription activation. Acetylation of H2A.Z at promoters of oncogenes has been linked to tumorigenesis. The mechanism is unknown. Here, we show that in triple negative breast cancer cells, H2A.Z bound to the promoter of the constitutively, weakly expressed cyclin D1 oncogene (CCND1), a key regulator of cellular proliferation. Depleting the pool of H2A.Z stimulated transcription of CCND1 in the absence of its cognate transcription factor, the estrogen receptor (ER). During activation of CCND1, H2A.Z was released from the transcription start site (TSS) and downstream enhancer (enh2) sequences. Concurrently, acetylation of H2A.Z, H3 and H4 at the TSS was increased but only H2A.Z was acetylated at enh2. Acetylation of H2A.Z required the Tip60 acetyltransferase to be associated with the activated CCND1 on both TSS and enh2 sites. Depletion of Tip60 prevented CCND1 activation. Chromosome conformation capture experiments (3C) revealed specific contacts between the TSS and enh2 chromatin regions. These results suggest that release of a histone H2A.Z-mediated repression loop activates CCND1 for transcription. Our findings open new avenues for controlling and understanding aberrant gene expression associated with tumorigenesis.
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Affiliation(s)
- M Dalvai
- Laboratoire de Biologie Moléculaire Eucaryote (LBME), University of Toulouse, Toulouse, France
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8
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Angeli L, Bellucci L, Botta M. Use of docking, cross docking and molecular dynamic simulations to rationalize the activity data of some S-dabos on wild-type and three mutant strains of reverse transcriptase. J Biotechnol 2010. [DOI: 10.1016/j.jbiotec.2010.08.272] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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9
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Sommerfreund J, Arhonditsis GB, Diamond ML, Frignani M, Capodaglio G, Gerino M, Bellucci L, Giuliani S, Mugnai C. Examination of the uncertainty in contaminant fate and transport modeling: a case study in the Venice Lagoon. Ecotoxicol Environ Saf 2010; 73:231-239. [PMID: 19493571 DOI: 10.1016/j.ecoenv.2009.05.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2009] [Revised: 05/02/2009] [Accepted: 05/04/2009] [Indexed: 05/27/2023]
Abstract
A Monte Carlo analysis is used to quantify environmental parametric uncertainty in a multi-segment, multi-chemical model of the Venice Lagoon. Scientific knowledge, expert judgment and observational data are used to formulate prior probability distributions that characterize the uncertainty pertaining to 43 environmental system parameters. The propagation of this uncertainty through the model is then assessed by a comparative analysis of the moments (central tendency, dispersion) of the model output distributions. We also apply principal component analysis in combination with correlation analysis to identify the most influential parameters, thereby gaining mechanistic insights into the ecosystem functioning. We found that modeled concentrations of Cu, Pb, OCDD/F and PCB-180 varied by up to an order of magnitude, exhibiting both contaminant- and site-specific variability. These distributions generally overlapped with the measured concentration ranges. We also found that the uncertainty of the contaminant concentrations in the Venice Lagoon was characterized by two modes of spatial variability, mainly driven by the local hydrodynamic regime, which separate the northern and central parts of the lagoon and the more isolated southern basin. While spatial contaminant gradients in the lagoon were primarily shaped by hydrology, our analysis also shows that the interplay amongst the in-place historical pollution in the central lagoon, the local suspended sediment concentrations and the sediment burial rates exerts significant control on the variability of the contaminant concentrations. We conclude that the probabilistic analysis presented herein is valuable for quantifying uncertainty and probing its cause in over-parameterized models, while some of our results can be used to dictate where additional data collection efforts should focus on and the directions that future model refinement should follow.
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Affiliation(s)
- J Sommerfreund
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
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10
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Tran NN, Leroy P, Bellucci L, Robert A, Nicolas A, Atkinson J, Capdeville-Atkinson C. Intracellular concentrations of fura-2 and fura-2/am in vascular smooth muscle cells following perfusion loading of fura-2/am in arterial segments. Cell Calcium 1995; 18:420-8. [PMID: 8581970 DOI: 10.1016/0143-4160(95)90057-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A new method for the determination of tissue concentrations of Fura-2 and Fura-2/AM was developed based upon acetonitrile extraction followed by RP-HPLC separation (using tetrahexylammonium as counter-ion), post-column alkaline hydrolysis of Fura-2/AM, and fluorimetric detection. The detection limit was 1.2 nM and 1 nM for Fura-2 and Fura-2/AM, respectively. When this technique was applied to perfusion-loaded segments of the rat tail artery, intracellular concentrations of Fura-2 determined by tissue disruption were 10 times those obtained by comparing the increase in fluorescence at the isoemissive point (following loading), with a calibration curve for Fura-2. Loading conditions of 90 min at [Fura-2/AM]e = 5 microM were optimal in terms of [Fura-2]i which attained a concentration not significantly different from [Fura-2/AM]e. Under such conditions, however, Fura-2/AM also accumulated in the arterial wall. Although incompletely de-esterified, Fura-2/AM metabolites produced by in vitro incubation of Fura-2/AM with pig liver esterases could be easily detected, fluorescent forms of Fura-2 with a different sensitivity for calcium were not detected in arterial extracts.
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Affiliation(s)
- N N Tran
- Laboratoire de Pharmacologie Cardio-vasculaire, URA CNRS 597, Faculté des Sciences Pharmaceutiques et Biologiques, Université Henri Poincaré-Nancy 1, France
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11
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Tran N, Leroy P, Bellucci L, Robert A, Nicolas A, Atkinson J, Capdeville-Atkinson C. Intracellular concentrations of Fura-2 and Fura-2/AM in vascular smooth muscle cells following perfusion loading of Fura-2/AM. Pharmacol Res 1995. [DOI: 10.1016/1043-6618(95)87082-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Pepe G, Bellucci L, Saccomanno F, Cataldi G, Giurazza G, Ortolani G, Frascolla N. [Epidemiological and clinical aspects of primary atypical pneumonia]. Arch Monaldi 1979; 34:251-8. [PMID: 122260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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