38 results on '"G. Callegaro"'
Search Results
2. Risk stratification for the safety of patients and hospital health workers during Covid-19 emergency
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P. Giuriato, R. C. Napolitano, P. Benini, M. Fioretto, A. Arseni, R. G. Callegaro, E. Zilli, A. Madia, D. Bonaldo, and D. Scibetta
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Sanitation ,Coronavirus disease 2019 (COVID-19) ,business.industry ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Public Health, Environmental and Occupational Health ,medicine.disease ,Intensive care unit ,law.invention ,5.A. Oral session: Effects of the Covid-19 pandemic on health systems ,Patient safety ,Health services ,law ,Risk stratification ,medicine ,AcademicSubjects/MED00860 ,AcademicSubjects/SOC01210 ,Medical emergency ,business ,Personal protective equipment ,AcademicSubjects/SOC02610 ,Parallel Programme - Abstract
Covid-19 emergency has forced hospitals to face enormous organizational challenges in order to implement solutions to minimize the impact of the infection and guarantee at the same time the quality of health services provided and the safety of patients and health workers. ULSS 6 Euganea - Health Trust (District of Padua) has defined four levels of risk for Hospital Units (from the highest to the lowest risk: Red, Yellow, Green and White) based on the following parameters: type of patients hospitalized (SARS-CoV-2 positive, Covid-like, negative), type of health services provided, time of assistance and care for hospitalized patient. This risk stratification in the Hospital of Cittadella - ULSS 6 Euganea has been applied to different contexts, such as distribution of personal protective equipment, health surveillance, frequency of cleaning and sanitation. Since February 21 (first confirmed case in Veneto Region), in the Hospital of Cittadella personal protective equipment has been delivered daily to health workers; the quantity and quality of devices provided have been carefully monitored, with particular regard to high-risk settings (Red Areas: Intensive Care Unit, Emergency Room, Covid Wards, Operating Room, Radiology, swab samples Area, Morgue). The performance of nasopharyngeal swabs has been periodically organized for every health worker, according to the level of risk of their Unit: every 10 days for Red Areas, every 20 days for Yellow and Green Areas, every 30 days for White Areas. The frequency of cleaning and sanitation has been intensified in Red and Yellow Areas, following the guidelines released by the World Health Organization. The definition of four levels of risk for Hospital Units is proving to be a useful and flexible tool in the management of Covid-19 emergency; further research in the next months needs to be made to assess the impact of risk stratification on the different aspects covered (ex. number of health workers infected). Key messages Covid-19 emergency has forced hospital to face enormous organizational challenges to minimize the impact of the infection and guarantee the safety of patients and health workers. The definition of four levels of risk for Hospital Units is proving to be a useful and flexible tool in the management of Covid-19 emergency.
- Published
- 2020
3. Epoxy Nanocomposites Based on Silylated Montmorillonite: Effect of the Coupling Agents Structure on the Mechanical Properties
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F. Piscitelli, Eugenio Amendola, M. Lavorgna, V. Romeo, A.M. Scamardella, and G. Callegaro
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chemistry.chemical_classification ,Materials science ,Polymer nanocomposite ,Sonication ,Intercalation (chemistry) ,Epoxy ,Polymer ,Nanoindentation ,chemistry.chemical_compound ,Montmorillonite ,chemistry ,visual_art ,visual_art.visual_art_medium ,Composite material ,Alkyl - Abstract
MMT clay-based polymer nanocomposites have been widely studied because of their low cost and unique characteristics, as well as their applications in commercial sectors. The aim of this work was to evaluate the effect of MMT silylated by 3-aminopropyltriethoxysilane and N-(2-aminoethyl)-3-aminopropyltrimethoxysilane on the mechanical behaviour of MMT/epoxy nanocomposites by evaluation of dynamical mechanical analysis and nanoindentation technique. The silicate clay layers were dispersed in the epoxy matrix by sonication process obtaining the intercalation of the epoxy resin inside the inorganic galleries of MMT. The results showed that the MMT modified with N-(2-aminoethyl)-3- aminopropyltrimethoxysilane, which is characterized by the longer alkyl functional group, exhibits an higher compatibility with polymer matrix and improved mechanical properties.
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- 2012
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4. Innovative Poly(Butylene Terephthalate) Based Nanocomposites: a Preliminary Investigation
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Domenico Acierno, Eugenio Amendola, G. Callegaro, and G. Napolitano
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Poly(Butylene Terephthalate) ,chemistry.chemical_classification ,Nanocomposite ,Materials science ,Polymers and Plastics ,Organic Chemistry ,Intercalation (chemistry) ,organoclay ,Polymer ,Condensed Matter Physics ,Silicate ,Nanocomposites ,chemistry.chemical_compound ,chemistry ,Compounding ,Materials Chemistry ,Organoclay ,Extrusion ,Composite material ,PBT - Abstract
Summary: A polymer-clay nanocomposite based on Poly(butyleneterephthalate)(PBT) and an innovative organoclay has been synthesized via intercalation ofBis(hydroxyethyl terephthalate) (BHET) in Na-Montmorillonite layers. Chemical andphysical properties of this nanocomposite have been studied in comparison to otherPBT/nanocomposites based on two commercial organoclay: Cloisite 25A and SomasifMEE. Nanocomposites have beenprepared viamelt compounding using atwin-screwextruder, with extrusion rate of 150 rpm. Samples were characterized by usingwide-angle X-ray diffraction, TEM, thermal and mechanical analysis. Introduction In recent years polymer/layered silicate(PLS) nanocomposites have attractingincreasing interest in academia and indus-try because of their remarkable improve-mentsinmaterialpropertieswithrespecttopristine polymer or conventional micro andmacro-composites. They exhibit high mod-uli, [1–3] increased strength and heat resis-tance, [4] decreasedgaspermeability [5–7] andflammability.
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- 2007
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5. Clay Modification with bis-2hydroxyethyl terephthalate for PET/Nanocomposites
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ACIERNO, DOMENICO, E. AMENDOLA, G. CALLEGARO, Acierno, Domenico, E., Amendola, and G., Callegaro
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nanocomposite ,polymer ,polyester ,clay - Published
- 2007
6. Poly(butylene terephthalate) nanocomposites containing organoclay prepared via intercalation with polymer precursor
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D. Acierno, E. Amendola, G. Callegaro, G. Napolitano, Acierno, Domenico, E., Amendola, G., Callegaro, and G., Napolitano
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- 2006
7. [Management of gastrointestinal bleeding in Veneto Region, Italy]
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M, Saia, G, Callegaro, C, Pilerci, and F, Pietrobon
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Adult ,Aged, 80 and over ,Male ,Adolescent ,Incidence ,Infant, Newborn ,Infant ,Length of Stay ,Middle Aged ,Patient Discharge ,Survival Rate ,Italy ,Child, Preschool ,Humans ,Female ,Hospital Mortality ,Child ,Gastrointestinal Hemorrhage ,Aged ,Retrospective Studies - Abstract
Gastrointestinal bleeding (GB) is still a common medical emergency and an important cause of morbidity and mortality. There is clear evidence that early endoscopic intervention is effective in reducing mortality, length of stay and surgery procedures utilization in high-risk patients. In the last decades advances in medical practice and in endoscopic technology have influenced the management of GB, but their impact on the incidence and mortality is unclear. The aim of this study was to evaluate retrospectively time trends (2000-2007) in GB hospitalizations and in-hospital mortality, and describe the organization of endoscopic services of Veneto region, Italy. Data were collected from regional database of hospital discharge from 2000 to 2007 and all patients with an ICD 9-CM discharge diagnosis of GB were included. Overall hospitalization and in-hospital mortality rates were respectively 99.3 and 4.5 per 100.000 inh./year, the last being related to older age. Surgery procedures utilization was 5%. Hospitalization and mortality rates decreased significantly over years, probably owing to advances in the acute management of GB, principally represented by endoscopic procedures.
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- 2011
8. CLAY FUNCTIONALIZATION WITH DIFFERENT AMINOSILANES FOR NANOCOMPOSITES PREPARATION
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F. Piscitelli, G. Callegaro, M. Lavorgna, E. Amendola, G. Mensitieri, D. Acierno, Alberto D’Amore, Domenico Acierno, and Luigi Grassia
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chemistry.chemical_compound ,Nanocomposite ,Silanes ,Materials science ,chemistry ,Chemical engineering ,Surface modification ,Gravimetric analysis ,Polymer blend ,Adhesive ,Composite material ,Fourier transform infrared spectroscopy ,Silane - Abstract
This study describes the prepn. and the characterization of nanocomposites obtained by dispersion of amino-functionalised clays in DGEBA based adhesives. The amino-functionalised clays were obtained through silylation of Na+ Cloisite with three different aminosilanes such as A1100 (3-aminopropyltriethoxysilane), A1120 (N(beta-aminoethyl)y-aminopropyltrimethoxy-silane) and A1130 (Triaminofunctional silane). The presence of amino moieties on the layered silicates was confirmed by FTIR, thermal gravimetric and X-ray diffraction anal. In particular it was evidenced that the d-spacing between platelets constituting the tactoid filler increases as shorter is the org. chains of the different silanes. The nanocomposites obtained by dispersing the amino functionalised clays into a com. epoxy adhesive were characterised in terms of thermal and mech. behavior. (c) 2008 American Institute of Physics.
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- 2008
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9. Investigation on Poly(butylene terephthalate) (PBT) nanocomposites prepared with Bis(hydroxyethyl terephthale) (BHET) modified clay
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IM - L 31.D. Acierno, E. Amendola, and G. Callegaro
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- 2008
10. Poly(ButyleneTerephthalate) nanocomposites containing organoclay prepared via intercalation with polymer precursor
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D. Acierno, E. Amendola, G. Callegaro, and G. Napolitano
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- 2006
11. [Somatomedin, growth and nutritional status]
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J O, Tirapegui, M A, Cardoso, and M da G, Callegaro
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Somatomedins ,Animals ,Humans ,Nutritional Status ,Dietary Proteins ,Growth ,Protein-Energy Malnutrition ,Rats - Abstract
Serum somatomedins, or insulin-like growth factor(s) (IGF), originally characterized as primarily GH-dependent peptides, were found to also be dependent on insulin levels and nutritional status. Four properties characterize somatomedin peptides: their concentrations in serum are growth hormone dependent; they possess insulin actions in extraskeletal tissues; they promote the incorporation of sulfate into proteoglycans of cartilage; and they stimulate DNA synthesis and cell multiplication in certain types of cultured cells. Reduced somatomedin C levels are found in children with severe protein-energy malnutrition. Plasma concentration of growth hormone and cortisol are both elevated and there are low levels of insulin and somatomedin C. There is evidence that the ability of somatomedin C to stimulate cartilage is modulated by somatomedin inhibitor, factor that may act to limit growth in conditions of hormonal and/or nutritional deficiency. Dietary energy and protein appears to be particularly important for both generation of somatomedins and their action on growing cartilage. Measurement of somatomedins C concentration shows promise as a means for monitoring the response of malnourished patients and rats to nutrition repletion.
- Published
- 1990
12. Clay functonalization with different aminosilanes for nanocomposites preparation
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Piscitelli, F., Callegaro, G., Lavorgna, M., Amendola, E., Mensitieri, G, Acierno, Domenico, F., Piscitelli, G., Callegaro, M., Lavorgna, E., Amendola, Mensitieri, Giuseppe, and Acierno, Domenico
- Published
- 2008
13. The integrated stress response-related expression of CHOP due to mitochondrial toxicity is a warning sign for DILI liability.
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Vlasveld M, Callegaro G, Fisher C, Eakins J, Walker P, Lok S, van Oost S, de Jong B, Pellegrino-Coppola D, Burger G, Wink S, and van de Water B
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- Humans, Hep G2 Cells, Oxidative Stress, Gene Expression Profiling, Hepatocytes metabolism, Chemical and Drug Induced Liver Injury genetics, Chemical and Drug Induced Liver Injury metabolism
- Abstract
Background and Aims: Drug-induced liver injury (DILI) is one of the most frequent reasons for failure of drugs in clinical trials or market withdrawal. Early assessment of DILI risk remains a major challenge during drug development. Here, we present a mechanism-based weight-of-evidence approach able to identify certain candidate compounds with DILI liabilities due to mitochondrial toxicity., Methods: A total of 1587 FDA-approved drugs and 378 kinase inhibitors were screened for cellular stress response activation associated with DILI using an imaging-based HepG2 BAC-GFP reporter platform including the integrated stress response (CHOP), DNA damage response (P21) and oxidative stress response (SRXN1)., Results: In total 389, 219 and 104 drugs were able to induce CHOP-GFP, P21-GFP and SRXN1-GFP expression at 50 μM respectively. Concentration response analysis identified 154 FDA-approved drugs as critical CHOP-GFP inducers. Based on predicted and observed (pre-)clinical DILI liabilities of these drugs, nine antimycotic drugs (e.g. butoconazole, miconazole, tioconazole) and 13 central nervous system (CNS) agents (e.g. duloxetine, fluoxetine) were selected for transcriptomic evaluation using whole-genome RNA-sequencing of primary human hepatocytes. Gene network analysis uncovered mitochondrial processes, NRF2 signalling and xenobiotic metabolism as most affected by the antimycotic drugs and CNS agents. Both the selected antimycotics and CNS agents caused impairment of mitochondrial oxygen consumption in both HepG2 and primary human hepatocytes., Conclusions: Together, the results suggest that early pre-clinical screening for CHOP expression could indicate liability of mitochondrial toxicity in the context of DILI, and, therefore, could serve as an important warning signal to consider during decision-making in drug development., (© 2024 The Authors. Liver International published by John Wiley & Sons Ltd.)
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- 2024
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14. A network-based transcriptomic landscape of HepG2 cells uncovering causal gene-cytotoxicity interactions underlying drug-induced liver injury.
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Wijaya LS, Gabor A, Pot IE, van de Have L, Saez-Rodriguez J, Stevens JL, Le Dévédec SE, Callegaro G, and van de Water B
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- Humans, Hep G2 Cells, Gene Expression Profiling, Gene Regulatory Networks, Transcriptome, Chemical and Drug Induced Liver Injury genetics
- Abstract
Drug-induced liver injury (DILI) remains the main reason for drug development attritions largely due to poor mechanistic understanding. Toxicogenomic to interrogate the mechanism of DILI has been broadly performed. Gene coregulation network-based transcriptome analysis is a bioinformatics approach that potentially contributes to improve mechanistic interpretation of toxicogenomic data. Here we performed an extensive concentration time course response-toxicogenomic study in the HepG2 cell line exposed to 20 DILI compounds, 7 reference compounds for stress response pathways, and 10 agonists for cytokines and growth factor receptors. We performed whole transcriptome targeted RNA sequencing to more than 500 conditions and applied weighted gene coregulated network analysis to the transcriptomics data followed by the identification of gene coregulated networks (modules) that were strongly modulated upon the exposure of DILI compounds. Preservation analysis on the module responses of HepG2 and PHH demonstrated highly preserved adaptive stress response gene coregulated networks. We correlated gene coregulated networks with cell death onset and causal relationships of 67 critical target genes of these modules with the onset of cell death was evaluated using RNA interference screening. We identified GTPBP2, HSPA1B, IRF1, SIRT1, and TSC22D3 as essential modulators of DILI compound-induced cell death. These genes were also induced by DILI compounds in PHH. Altogether, we demonstrate the application of large transcriptome datasets combined with network-based analysis and biological validation to uncover the candidate determinants of DILI., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Society of Toxicology.)
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- 2024
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15. eTRANSAFE: data science to empower translational safety assessment.
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Sanz F, Pognan F, Steger-Hartmann T, Díaz C, Asakura S, Amberg A, Bécourt-Lhote N, Blomberg N, Bosc N, Briggs K, Bringezu F, Brulle-Wohlhueter C, Brunak S, Bueters R, Callegaro G, Capella-Gutierrez S, Centeno E, Corvi J, Cronin MTD, Drew P, Duchateau-Nguyen G, Ecker GF, Escher S, Felix E, Ferreiro M, Frericks M, Furlong LI, Geiger R, George C, Grandits M, Ivanov-Draganov D, Kilgour-Christie J, Kiziloren T, Kors JA, Koyama N, Kreuchwig A, Leach AR, Mayer MA, Monecke P, Muster W, Nakazawa CM, Nicholson G, Parry R, Pastor M, Piñero J, Oberhauser N, Ramírez-Anguita JM, Rodrigo A, Smajic A, Schaefer M, Schieferdecker S, Soininen I, Terricabras E, Trairatphisan P, Turner SC, Valencia A, van de Water B, van der Lei JL, van Mulligen EM, Vock E, and Wilkinson D
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- Humans, Data Science, Translational Research, Biomedical
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- 2023
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16. Identifying multiscale translational safety biomarkers using a network-based systems approach.
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Callegaro G, Schimming JP, Piñero González J, Kunnen SJ, Wijaya L, Trairatphisan P, van den Berk L, Beetsma K, Furlong LI, Sutherland JJ, Mollon J, Stevens JL, and van de Water B
- Abstract
Animal testing is the current standard for drug and chemicals safety assessment, but hazards translation to human is uncertain. Human in vitro models can address the species translation but might not replicate in vivo complexity. Herein, we propose a network-based method addressing these translational multiscale problems that derives in vivo liver injury biomarkers applicable to in vitro human early safety screening. We applied weighted correlation network analysis (WGCNA) to a large rat liver transcriptomic dataset to obtain co-regulated gene clusters (modules). We identified modules statistically associated with liver pathologies, including a module enriched for ATF4-regulated genes as associated with the occurrence of hepatocellular single-cell necrosis, and as preserved in human liver in vitro models. Within the module, we identified TRIB3 and MTHFD2 as a novel candidate stress biomarkers, and developed and used BAC-eGFPHepG2 reporters in a compound screening, identifying compounds showing ATF4-dependent stress response and potential early safety signals., Competing Interests: L.I.F. and J.P.G. are employees and shareholders of MedBioInformatics Solutions SL., (© 2023 The Author(s).)
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- 2023
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17. Application of high-throughput transcriptomics for mechanism-based biological read-across of short-chain carboxylic acid analogues of valproic acid.
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Vrijenhoek NG, Wehr MM, Kunnen SJ, Wijaya LS, Callegaro G, Moné MJ, Escher SE, and Van de Water B
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- Carboxylic Acids metabolism, Hepatocytes metabolism, Liver, Transcriptome, Valproic Acid metabolism, Valproic Acid toxicity
- Abstract
Chemical read-across is commonly evaluated without specific knowledge of the biological mechanisms leading to observed adverse outcomes in vivo. Integrating data that indicate shared modes of action in humans will strengthen read-across cases. Here we studied transcriptomic responses of primary human hepatocytes (PHH) to a large panel of carboxylic acids to include detailed mode-of-action data as a proof-of-concept for read-across in risk assessment. In rodents, some carboxylic acids, including valproic acid (VPA), are known to cause hepatic steatosis, whereas others do not. We investigated transcriptomics responses of PHHs exposed for 24 h to 18 structurally different VPA analogues in a concentration range to determine biological similarity in relation to in vivo steatotic potential. Using a targeted high-throughput screening assay, we assessed the differential expression of ~3,000 genes covering relevant biological pathways. Differentially expressed gene analysis revealed differences in potency of carboxylic acids, and expression patterns were highly similar for structurally similar compounds. Strong clustering occurred for steatosis-positive versus steatosis-negative carboxylic acids. To quantitatively define biological read-across, we combined pathway analysis and weighted gene co-expression network analysis. Active carboxylic acids displayed high similarity in gene network modulation. Importantly, free fatty acid synthesis modulation and stress pathway responses are affected by active carboxylic acids, providing coherent mechanistic underpinning for our findings. Our work shows that transcriptomic analysis of cultured human hepatocytes can reinforce the prediction of liver injury outcome based on quantitative and mechanistic biological data and support its application in read-across.
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- 2022
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18. Mapping the cellular response to electron transport chain inhibitors reveals selective signaling networks triggered by mitochondrial perturbation.
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van der Stel W, Yang H, Vrijenhoek NG, Schimming JP, Callegaro G, Carta G, Darici S, Delp J, Forsby A, White A, le Dévédec S, Leist M, Jennings P, Beltman JB, van de Water B, and Danen EHJ
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- Electron Transport, Hep G2 Cells, Hepatocytes, Humans, Electron Transport Complex I, Mitochondria
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Mitochondrial perturbation is a key event in chemical-induced organ toxicities that is incompletely understood. Here, we studied how electron transport chain (ETC) complex I, II, or III (CI, CII and CIII) inhibitors affect mitochondrial functionality, stress response activation, and cell viability using a combination of high-content imaging and TempO-Seq in HepG2 hepatocyte cells. CI and CIII inhibitors perturbed mitochondrial membrane potential (MMP) and mitochondrial and cellular ATP levels in a concentration- and time-dependent fashion and, under conditions preventing a switch to glycolysis attenuated cell viability, whereas CII inhibitors had no effect. TempO-Seq analysis of changes in mRNA expression pointed to a shared cellular response to CI and CIII inhibition. First, to define specific ETC inhibition responses, a gene set responsive toward ETC inhibition (and not to genotoxic, oxidative, or endoplasmic reticulum stress) was identified using targeted TempO-Seq in HepG2. Silencing of one of these genes, NOS3, exacerbated the impact of CI and CIII inhibitors on cell viability, indicating its functional implication in cellular responses to mitochondrial stress. Then by monitoring dynamic responses to ETC inhibition using a HepG2 GFP reporter panel for different classes of stress response pathways and applying pathway and gene network analysis to TempO-Seq data, we looked for downstream cellular events of ETC inhibition and identified the amino acid response (AAR) as being triggered in HepG2 by ETC inhibition. Through in silico approaches we provide evidence indicating that a similar AAR is associated with exposure to mitochondrial toxicants in primary human hepatocytes. Altogether, we (i) unravel quantitative, time- and concentration-resolved cellular responses to mitochondrial perturbation, (ii) identify a gene set associated with adaptation to exposure to active ETC inhibitors, and (iii) show that ER stress and an AAR accompany ETC inhibition in HepG2 and primary hepatocytes., (© 2021. The Author(s).)
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- 2022
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19. The human hepatocyte TXG-MAPr: gene co-expression network modules to support mechanism-based risk assessment.
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Callegaro G, Kunnen SJ, Trairatphisan P, Grosdidier S, Niemeijer M, den Hollander W, Guney E, Piñero Gonzalez J, Furlong L, Webster YW, Saez-Rodriguez J, Sutherland JJ, Mollon J, Stevens JL, and van de Water B
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- Acetaminophen toxicity, Animals, Chemical and Drug Induced Liver Injury genetics, Cyclosporine toxicity, Datasets as Topic, Endoplasmic Reticulum Stress drug effects, Gene Expression Profiling, Gene Regulatory Networks, Hepatocytes pathology, Humans, Oxidative Stress drug effects, Rats, Species Specificity, Tunicamycin toxicity, Chemical and Drug Induced Liver Injury etiology, Hepatocytes drug effects, Risk Assessment methods, Toxicogenetics methods
- Abstract
Mechanism-based risk assessment is urged to advance and fully permeate into current safety assessment practices, possibly at early phases of drug safety testing. Toxicogenomics is a promising source of mechanisms-revealing data, but interpretative analysis tools specific for the testing systems (e.g. hepatocytes) are lacking. In this study, we present the TXG-MAPr webtool (available at https://txg-mapr.eu/WGCNA_PHH/TGGATEs_PHH/ ), an R-Shiny-based implementation of weighted gene co-expression network analysis (WGCNA) obtained from the Primary Human Hepatocytes (PHH) TG-GATEs dataset. The 398 gene co-expression networks (modules) were annotated with functional information (pathway enrichment, transcription factor) to reveal their mechanistic interpretation. Several well-known stress response pathways were captured in the modules, were perturbed by specific stressors and showed preservation in rat systems (rat primary hepatocytes and rat in vivo liver), with the exception of DNA damage and oxidative stress responses. A subset of 87 well-annotated and preserved modules was used to evaluate mechanisms of toxicity of endoplasmic reticulum (ER) stress and oxidative stress inducers, including cyclosporine A, tunicamycin and acetaminophen. In addition, module responses can be calculated from external datasets obtained with different hepatocyte cells and platforms, including targeted RNA-seq data, therefore, imputing biological responses from a limited gene set. As another application, donors' sensitivity towards tunicamycin was investigated with the TXG-MAPr, identifying higher basal level of intrinsic immune response in donors with pre-existing liver pathology. In conclusion, we demonstrated that gene co-expression analysis coupled to an interactive visualization environment, the TXG-MAPr, is a promising approach to achieve mechanistic relevant, cross-species and cross-platform evaluation of toxicogenomic data., (© 2021. The Author(s).)
- Published
- 2021
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20. The eTRANSAFE Project on Translational Safety Assessment through Integrative Knowledge Management: Achievements and Perspectives.
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Pognan F, Steger-Hartmann T, Díaz C, Blomberg N, Bringezu F, Briggs K, Callegaro G, Capella-Gutierrez S, Centeno E, Corvi J, Drew P, Drewe WC, Fernández JM, Furlong LI, Guney E, Kors JA, Mayer MA, Pastor M, Piñero J, Ramírez-Anguita JM, Ronzano F, Rowell P, Saüch-Pitarch J, Valencia A, van de Water B, van der Lei J, van Mulligen E, and Sanz F
- Abstract
eTRANSAFE is a research project funded within the Innovative Medicines Initiative (IMI), which aims at developing integrated databases and computational tools (the eTRANSAFE ToxHub) that support the translational safety assessment of new drugs by using legacy data provided by the pharmaceutical companies that participate in the project. The project objectives include the development of databases containing preclinical and clinical data, computational systems for translational analysis including tools for data query, analysis and visualization, as well as computational models to explain and predict drug safety events.
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- 2021
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21. An ensemble learning approach for modeling the systems biology of drug-induced injury.
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Aguirre-Plans J, Piñero J, Souza T, Callegaro G, Kunnen SJ, Sanz F, Fernandez-Fuentes N, Furlong LI, Guney E, and Oliva B
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- Humans, Models, Biological, Chemical and Drug Induced Liver Injury, Drug-Related Side Effects and Adverse Reactions, Machine Learning, Pharmaceutical Preparations chemistry, Systems Biology
- Abstract
Background: Drug-induced liver injury (DILI) is an adverse reaction caused by the intake of drugs of common use that produces liver damage. The impact of DILI is estimated to affect around 20 in 100,000 inhabitants worldwide each year. Despite being one of the main causes of liver failure, the pathophysiology and mechanisms of DILI are poorly understood. In the present study, we developed an ensemble learning approach based on different features (CMap gene expression, chemical structures, drug targets) to predict drugs that might cause DILI and gain a better understanding of the mechanisms linked to the adverse reaction., Results: We searched for gene signatures in CMap gene expression data by using two approaches: phenotype-gene associations data from DisGeNET, and a non-parametric test comparing gene expression of DILI-Concern and No-DILI-Concern drugs (as per DILIrank definitions). The average accuracy of the classifiers in both approaches was 69%. We used chemical structures as features, obtaining an accuracy of 65%. The combination of both types of features produced an accuracy around 63%, but improved the independent hold-out test up to 67%. The use of drug-target associations as feature obtained the best accuracy (70%) in the independent hold-out test., Conclusions: When using CMap gene expression data, searching for a specific gene signature among the landmark genes improves the quality of the classifiers, but it is still limited by the intrinsic noise of the dataset. When using chemical structures as a feature, the structural diversity of the known DILI-causing drugs hampers the prediction, which is a similar problem as for the use of gene expression information. The combination of both features did not improve the quality of the classifiers but increased the robustness as shown on independent hold-out tests. The use of drug-target associations as feature improved the prediction, specially the specificity, and the results were comparable to previous research studies.
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- 2021
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22. In vitro and bioinformatics mechanistic-based approach for cadmium carcinogenicity understanding.
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Oldani M, Fabbri M, Melchioretto P, Callegaro G, Fusi P, Gribaldo L, Forcella M, and Urani C
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- Animals, Carcinogenesis chemically induced, Carcinogenesis genetics, Cell Line, Cell Transformation, Neoplastic genetics, Computational Biology, Cytokines genetics, Gene Expression Regulation, Neoplastic drug effects, Mice, Cadmium toxicity, Carcinogens toxicity
- Abstract
Cadmium is a toxic metal able to enter the cells through channels and transport pathways dedicated to essential ions, leading, among others, to the dysregulation of divalent ions homeostasis. Despite its recognized human carcinogenicity, the mechanisms are still under investigation. A powerful tool for mechanistic studies of carcinogenesis is the Cell Transformation Assay (CTA). We have isolated and characterized by whole genome microarray and bioinformatics analysis of differentially expressed genes (DEGs) cadmium-transformed cells from different foci (F1, F2, and F3) at the end of CTA (6 weeks). The systematic analysis of up- and down-regulated transcripts and the comparison of DEGs in transformed cells evidence different functional targets and the complex picture of cadmium-induced transformation. Only 34 in common DEGs are found in cells from all foci, and among these, only 4 genes are jointly up-regulated (Ccl2, Ccl5, IL6 and Spp1), all responsible for cytokines/chemokines coding. Most in common DEGs are down-regulated, suggesting that the switching-off of specific functions plays a major role in this process. In addition, the comparison of dysregulated pathways immediately after cadmium treatment with those in transformed cells provides a valuable means to the comprehension of the overall process., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2020
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23. High-throughput confocal imaging of differentiated 3D liver-like spheroid cellular stress response reporters for identification of drug-induced liver injury liability.
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Hiemstra S, Ramaiahgari SC, Wink S, Callegaro G, Coonen M, Meerman J, Jennen D, van den Nieuwendijk K, Dankers A, Snoeys J, de Bont H, Price L, and van de Water B
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- Cell Differentiation, Chemical and Drug Induced Liver Injury etiology, Chemical and Drug Induced Liver Injury genetics, DNA Damage drug effects, Genes, Reporter genetics, Green Fluorescent Proteins genetics, Hep G2 Cells, Hepatocytes pathology, High-Throughput Screening Assays methods, Humans, Microscopy, Confocal methods, Spheroids, Cellular pathology, Stress, Physiological drug effects, Chemical and Drug Induced Liver Injury pathology, Hepatocytes drug effects, Spheroids, Cellular drug effects
- Abstract
Adaptive stress response pathways play a key role in the switch between adaptation and adversity, and are important in drug-induced liver injury. Previously, we have established an HepG2 fluorescent protein reporter platform to monitor adaptive stress response activation following drug treatment. HepG2 cells are often used in high-throughput primary toxicity screening, but metabolizing capacity in these cells is low and repeated dose toxicity testing inherently difficult. Here, we applied our bacterial artificial chromosome-based GFP reporter cell lines representing Nrf2 activation (Srxn1-GFP and NQO1-GFP), unfolded protein response (BiP-GFP and Chop-GFP), and DNA damage response (p21-GFP and Btg2-GFP) as long-term differentiated 3D liver-like spheroid cultures. All HepG2 GFP reporter lines differentiated into 3D spheroids similar to wild-type HepG2 cells. We systematically optimized the automated imaging and quantification of GFP reporter activity in individual spheroids using high-throughput confocal microscopy with a reference set of DILI compounds that activate these three stress response pathways at the transcriptional level in primary human hepatocytes. A panel of 33 compounds with established DILI liability was further tested in these six 3D GFP reporters in single 48 h treatment or 6 day daily repeated treatment. Strongest stress response activation was observed after 6-day repeated treatment, with the BiP and Srxn1-GFP reporters being most responsive and identified particular severe-DILI-onset compounds. Compounds that showed no GFP reporter activation in two-dimensional (2D) monolayer demonstrated GFP reporter stress response activation in 3D spheroids. Our data indicate that the application of BAC-GFP HepG2 cellular stress reporters in differentiated 3D spheroids is a promising strategy for mechanism-based identification of compounds with liability for DILI.
- Published
- 2019
- Full Text
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24. Characterisation of the NRF2 transcriptional network and its response to chemical insult in primary human hepatocytes: implications for prediction of drug-induced liver injury.
- Author
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Copple IM, den Hollander W, Callegaro G, Mutter FE, Maggs JL, Schofield AL, Rainbow L, Fang Y, Sutherland JJ, Ellis EC, Ingelman-Sundberg M, Fenwick SW, Goldring CE, van de Water B, Stevens JL, and Park BK
- Subjects
- Cells, Cultured, Chemical and Drug Induced Liver Injury pathology, Gene Expression Regulation drug effects, Hepatocytes pathology, Humans, Isothiocyanates adverse effects, Kelch-Like ECH-Associated Protein 1 genetics, Oligonucleotide Array Sequence Analysis, Oxidative Stress drug effects, Oxidative Stress genetics, RNA, Small Interfering, Sulfoxides, Chemical and Drug Induced Liver Injury genetics, Gene Regulatory Networks drug effects, Hepatocytes drug effects, NF-E2-Related Factor 2 genetics
- Abstract
The transcription factor NRF2, governed by its repressor KEAP1, protects cells against oxidative stress. There is interest in modelling the NRF2 response to improve the prediction of clinical toxicities such as drug-induced liver injury (DILI). However, very little is known about the makeup of the NRF2 transcriptional network and its response to chemical perturbation in primary human hepatocytes (PHH), which are often used as a translational model for investigating DILI. Here, microarray analysis identified 108 transcripts (including several putative novel NRF2-regulated genes) that were both downregulated by siRNA targeting NRF2 and upregulated by siRNA targeting KEAP1 in PHH. Applying weighted gene co-expression network analysis (WGCNA) to transcriptomic data from the Open TG-GATES toxicogenomics repository (representing PHH exposed to 158 compounds) revealed four co-expressed gene sets or 'modules' enriched for these and other NRF2-associated genes. By classifying the 158 TG-GATES compounds based on published evidence, and employing the four modules as network perturbation metrics, we found that the activation of NRF2 is a very good indicator of the intrinsic biochemical reactivity of a compound (i.e. its propensity to cause direct chemical stress), with relatively high sensitivity, specificity, accuracy and positive/negative predictive values. We also found that NRF2 activation has lower sensitivity for the prediction of clinical DILI risk, although relatively high specificity and positive predictive values indicate that false positive detection rates are likely to be low in this setting. Underpinned by our comprehensive analysis, activation of the NRF2 network is one of several mechanism-based components that can be incorporated into holistic systems toxicology models to improve mechanistic understanding and preclinical prediction of DILI in man.
- Published
- 2019
- Full Text
- View/download PDF
25. Toxicogenomics applied to in vitro Cell Transformation Assay reveals mechanisms of early response to cadmium.
- Author
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Callegaro G, Forcella M, Melchioretto P, Frattini A, Gribaldo L, Fusi P, Fabbri M, and Urani C
- Subjects
- Animals, Carcinogens, Cell Line, Gene Expression Regulation drug effects, Glutathione Transferase metabolism, Metallothionein metabolism, Mice, Mice, Inbred C3H, Microarray Analysis, Receptors, Odorant drug effects, Receptors, Odorant genetics, Signal Transduction drug effects, Zinc metabolism, Cadmium toxicity, Cell Transformation, Neoplastic drug effects, Toxicogenetics methods
- Abstract
Cadmium is a well recognized carcinogen, primarily released into the environment by anthropogenic activities. In the effort to understand the early events responsible for cadmium carcinogenesis, we have used an in vitro biological system (the Cell Transformation Assay, CTA), that has been shown to closely model some key stages of the conversion of normal cells into malignant ones. Cadmium-triggered early responses in CTA were analysed through microarray-based toxicogenomics. Metallothioneins represent the earliest cell response, together with Slc30a1 encoding for a ZnT-1 zinc exporter. Other genes were found to be up-regulated in the first 24 h following Cd administration: phospatidylinositol-4-phospate 5-kinase alpha (Pip5k1a), glutathione S-transferase (Gstα 1-3), Gdf15 and aldolase. However, after the exposure, a number of genes expressing zinc proteins were found to be down-regulated, among which were many olfactory receptors (ORs) coding genes. Cd administration also promoted massive Zn release inside the cell that could be related to moonlighting activities of regulated genes (proteins). On the whole our data suggest that, despite the early involvement of defence mechanisms (metallothionein and GST), Cd-triggered Zn release, as well as Cd interference with different proteins, may lead to gene expression alterations which later induce metabolic changes, directing the cells towards uncontrolled growth., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
- Published
- 2018
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- View/download PDF
26. A comprehensive statistical classifier of foci in the cell transformation assay for carcinogenicity testing.
- Author
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Callegaro G, Malkoc K, Corvi R, Urani C, and Stefanini FM
- Subjects
- Algorithms, Animals, BALB 3T3 Cells, Bayes Theorem, Entropy, Image Processing, Computer-Assisted, Mice, Models, Biological, Mutagens toxicity, Carcinogenicity Tests classification, Cell Transformation, Neoplastic classification
- Abstract
The identification of the carcinogenic risk of chemicals is currently mainly based on animal studies. The in vitro Cell Transformation Assays (CTAs) are a promising alternative to be considered in an integrated approach. CTAs measure the induction of foci of transformed cells. CTAs model key stages of the in vivo neoplastic process and are able to detect both genotoxic and some non-genotoxic compounds, being the only in vitro method able to deal with the latter. Despite their favorable features, CTAs can be further improved, especially reducing the possible subjectivity arising from the last phase of the protocol, namely visual scoring of foci using coded morphological features. By taking advantage of digital image analysis, the aim of our work is to translate morphological features into statistical descriptors of foci images, and to use them to mimic the classification performances of the visual scorer to discriminate between transformed and non-transformed foci. Here we present a classifier based on five descriptors trained on a dataset of 1364 foci, obtained with different compounds and concentrations. Our classifier showed accuracy, sensitivity and specificity equal to 0.77 and an area under the curve (AUC) of 0.84. The presented classifier outperforms a previously published model., (Copyright © 2017 Elsevier Ltd. All rights reserved.)
- Published
- 2017
- Full Text
- View/download PDF
27. Relationship between increasing concentrations of two carcinogens and statistical image descriptors of foci morphology in the cell transformation assay.
- Author
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Callegaro G, Corvi R, Salovaara S, Urani C, and Stefanini FM
- Subjects
- Animals, BALB 3T3 Cells, Benzo(a)pyrene toxicity, Carcinogenicity Tests methods, Carcinogenicity Tests statistics & numerical data, Dose-Response Relationship, Drug, Mice, Microscopy methods, Microscopy statistics & numerical data, Nickel toxicity, Carcinogens toxicity, Cell Transformation, Neoplastic drug effects, Cell Transformation, Neoplastic pathology, Data Interpretation, Statistical, Image Interpretation, Computer-Assisted
- Abstract
Cell Transformation Assays (CTAs) have long been proposed for the identification of chemical carcinogenicity potential. The endpoint of these in vitro assays is represented by the phenotypic alterations in cultured cells, which are characterized by the change from the non-transformed to the transformed phenotype. Despite the wide fields of application and the numerous advantages of CTAs, their use in regulatory toxicology has been limited in part due to concerns about the subjective nature of visual scoring, i.e. the step in which transformed colonies or foci are evaluated through morphological features. An objective evaluation of morphological features has been previously obtained through automated digital processing of foci images to extract the value of three statistical image descriptors. In this study a further potential of the CTA using BALB/c 3T3 cells is addressed by analysing the effect of increasing concentrations of two known carcinogens, benzo[a]pyrene and NiCl
2 , with different modes of action on foci morphology. The main result of our quantitative evaluation shows that the concentration of the considered carcinogens has an effect on foci morphology that is statistically significant for the mean of two among the three selected descriptors. Statistical significance also corresponds to visual relevance. The statistical analysis of variations in foci morphology due to concentration allowed to quantify morphological changes that can be visually appreciated but not precisely determined. Therefore, it has the potential of providing new quantitative parameters in CTAs, and of exploiting all the information encoded in foci. Copyright © 2016 John Wiley & Sons, Ltd., (Copyright © 2016 John Wiley & Sons, Ltd.)- Published
- 2017
- Full Text
- View/download PDF
28. Cadmium-transformed cells in the in vitro cell transformation assay reveal different proliferative behaviours and activated pathways.
- Author
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Forcella M, Callegaro G, Melchioretto P, Gribaldo L, Frattini M, Stefanini FM, Fusi P, and Urani C
- Subjects
- Animals, Biological Assay, Cell Line, Cell Proliferation drug effects, ErbB Receptors metabolism, MAP Kinase Signaling System drug effects, Mice, Proto-Oncogene Proteins c-akt metabolism, Cadmium Chloride toxicity, Cell Transformation, Neoplastic drug effects
- Abstract
The in vitro Cell Transformation Assay (CTA) is a powerful tool for mechanistic studies of carcinogenesis. The endpoint is the classification of transformed colonies (foci) by means of standard morphological features. To increase throughput and reliability of CTAs, one of the suggested follow-up activities is to exploit the comprehension of the mechanisms underlying cell transformation. To this end, we have performed CTAs testing CdCl2, a widespread environmental contaminant classified as a human carcinogen with the underlying mechanisms of action not completely understood. We have isolated and re-seeded the cells at the end (6weeks) of in vitro CTAs to further identify the biochemical pathways underlying the transformed phenotype of foci. Morphological evaluations and proliferative assays confirmed the loss of contact-inhibition and the higher proliferative rate of transformed clones. The biochemical analysis of EGFR pathway revealed that, despite the same initial carcinogenic stimulus (1μM CdCl2 for 24h), transformed clones are characterized by the activation of two different molecular pathways: proliferation (Erk activation) or survival (Akt activation). Our preliminary results on molecular characterization of cell clones from different foci could be exploited for CTAs improvement, supporting the comprehension of the in vivo process and complementing the morphological evaluation of foci., (Copyright © 2016. Published by Elsevier Ltd.)
- Published
- 2016
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29. An improved classification of foci for carcinogenicity testing by statistical descriptors.
- Author
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Callegaro G, Stefanini FM, Colacci A, Vaccari M, and Urani C
- Subjects
- Animals, Area Under Curve, BALB 3T3 Cells, Biological Assay, Carcinogenicity Tests, Carcinogens toxicity, Logistic Models, Mice, ROC Curve, Cell Transformation, Neoplastic, Image Interpretation, Computer-Assisted
- Abstract
Carcinogenesis is a multi-step process involving genetic alterations and non-genotoxic mechanisms. The in vitro cell transformation assay (CTA) is a promising tool for both genotoxic and non-genotoxic carcinogenesis. CTA relies on the ability of cells (e.g. BALB/c 3T3 mouse embryo fibroblasts) to develop a transformed phenotype after the treatment with suspected carcinogens. The classification of the transformed phenotype is based on coded morphological features, which are scored under a light microscope by trained experts. This procedure is time-consuming and somewhat prone to subjectivity. Herewith we provide a promising approach based on image analysis to support the scoring of malignant foci in BALB/c 3T3 CTA. The image analysis system is a quantitative approach, based on measuring features of malignant foci: dimension, multilayered growth, and invasivity into the surrounding monolayer of non-transformed cells. A logistic regression model was developed to estimate the probability for each focus to be transformed as a function of three statistical image descriptors. The estimated sensitivity of the derived classifier (untransformed against Type III) was 0.9, with an Area Under the Curve (AUC) value equal to 0.90 under the Receiver Operating Characteristics (ROC) curve., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
- Published
- 2015
- Full Text
- View/download PDF
30. Frequency and trends of hospital discharges against medical advice (DAMA) in a large administrative database.
- Author
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Saia M, Buja A, Mantoan D, Bertoncello C, Baldovin T, Callegaro G, and Baldo V
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Child, Child, Preschool, Cohort Studies, Counseling, Female, Hospitals statistics & numerical data, Humans, Infant, Infant, Newborn, Italy epidemiology, Male, Middle Aged, Patient Compliance, Patient Discharge trends, Population, Pregnancy, Retrospective Studies, Socioeconomic Factors, Young Adult, Patient Discharge statistics & numerical data
- Abstract
Objective: The aim of this research was to characterize hospitalizations associated with discharges against medical advice (DAMA) in a large, population-based data system., Materials and Methods: This was a retrospective cohort study on 11 436 500 hospital admissions. The hospital discharge records for residents of the Veneto region (north-east Italy) discharged from 2001 to 2012, from both public and accredited private hospitals, were considered. The DAMA rate was calculated by type of hospital admission, excluding patients who died. The time trend of the DAMA rate was charted from the average annual percent changes., Results: During the period considered, 66 549 DAMA were recorded, amounting to an overall DAMA rate of 6.0‰ admissions. Analyzing the diagnostic categories, admissions for substance abuse (drugs or alcohol) and dependence coincided with the highest DAMA rate (83.5‰), followed by poisoning (40.2‰), psychiatric disorders (24.7 ‰), traumas (21.1‰), HIV-related diseases (19.9‰), burns (10.5‰), and - for women - issues relating to pregnancy, childbirth and the postnatal period (11.2‰). The DAMA rate dropped from 6.72 to 5.55 from 2000 to 2008, then remained stable., Conclusion: The DAMA rate dropped slightly over the period considered. Several diagnostic categories are associated with a higher likelihood of patients leaving hospital against their doctor's advice.
- Published
- 2014
- Full Text
- View/download PDF
31. Increased rate of day surgery use for inguinal and femoral hernia repair in a decade of hospital admissions in the Veneto Region (north-east Italy): a record linkage study.
- Author
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Saia M, Mantoan D, Buja A, Bertoncello C, Baldovin T, Zanardo C, Callegaro G, and Baldo V
- Subjects
- Adult, Age Factors, Aged, Aged, 80 and over, Child, Child, Preschool, Female, Hospitalization statistics & numerical data, Humans, Infant, Infant, Newborn, Italy epidemiology, Male, Middle Aged, Sex Factors, Young Adult, Ambulatory Surgical Procedures statistics & numerical data, Hernia, Femoral surgery, Hernia, Inguinal surgery
- Abstract
Background: Worldwide, there has been a marked increase in the number of inguinal and femoral hernia repairs performed as day surgery procedures. This study aimed to outline the epidemiology of the procedures for repairing unilateral inguinal and femoral hernia in the Veneto Region, and to analyze the time trends and organizational appropriateness of these procedures., Methods: Drawing from the anonymous computerized database of hospital discharge records for the Veneto Region, we identified all unilateral groin hernia repair procedures completed in Veneto residents between 2000 and 2009 at both public and accredited private hospitals., Results: A total 141,329 hernias were repaired in the Veneto Region during the decade considered, with an annual rate of 291.2 per 100,000 population for inguinal hernia (IH) repairs and 11.2 per 100,000 population for femoral hernia (FH) repairs. Day surgery was used more for inguinal than for femoral hernia repairs, accounting for 76% and 43% (p< 0.05), respectively, of all hernia repair procedures completed during the period. The % of other than surgery hospital ordinary admissions (day surgery or ambulatory surgery) during the decade considered rose from 61.7% to 86.7% for IH and from 33.0% to 61.8% for FH., Conclusions: In the last decade, the Veneto Region has reduced the rate of ordinary hospital admissions for groin hernia repair with a view to improving the efficiency of the hospital network.
- Published
- 2013
- Full Text
- View/download PDF
32. Objective scoring of transformed foci in BALB/c 3T3 cell transformation assay by statistical image descriptors.
- Author
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Urani C, Corvi R, Callegaro G, and Stefanini FM
- Subjects
- Animals, BALB 3T3 Cells, Carcinogens toxicity, Data Interpretation, Statistical, Mice, Microscopy methods, Microscopy statistics & numerical data, Biological Assay statistics & numerical data, Cell Transformation, Neoplastic, Image Interpretation, Computer-Assisted
- Abstract
In vitro cell transformation assays (CTAs) have been shown to model important stages of in vivo carcinogenesis and have the potential to predict carcinogenicity in humans. Advantages of CTAs are their ability of revealing both genotoxic and non-genotoxic carcinogens while reducing both experimental costs and the number of animals used. The endpoint of the CTA is foci formation, and requires classification under light microscopy based on morphology. Thus current limitations for the wide adoption of the assay partially depend on a fair degree of subjectivity in foci scoring. An objective evaluation may be obtained after separating foci from background monolayer in the digital image, and quantifying values of statistical descriptors which are selected to capture eye-scored morphological features. The aim of this study was to develop statistical descriptors to be applied to transformed foci of BALB/c 3T3, which cover foci size, multilayering and invasive cell growth into the background monolayer. Proposed descriptors were applied to a database of 407 foci images to explore the numerical features, and to illustrate open problems and potential solutions., (Copyright © 2013 Elsevier Ltd. All rights reserved.)
- Published
- 2013
- Full Text
- View/download PDF
33. Time trend and variability of open versus laparoscopic cholecystectomy in patients with symptomatic gallstone disease.
- Author
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Saia M, Mantoan D, Buja A, Bertoncello C, Baldovin T, Callegaro G, and Baldo V
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Child, Child, Preschool, Cholecystectomy, Laparoscopic, Cholelithiasis epidemiology, Female, Hospital Mortality, Hospitalization statistics & numerical data, Humans, Infant, Italy epidemiology, Length of Stay statistics & numerical data, Male, Middle Aged, Postoperative Complications, Retrospective Studies, Treatment Outcome, Cholecystectomy methods, Cholelithiasis surgery
- Abstract
Background: The purpose of this study was to compare length of stay, as one of the efficacy indicators, and effectiveness, in terms of operative complications and mortality, between laparoscopic (LC) and open cholecystectomy, and to verify the 10-year temporal trends in the application of the LC technique in a large regional population., Methods: This was a retrospective cohort study based on 73,853 hospital discharge records of cholecystectomies for gallstone disease (GD) in residents of the Veneto from 2001 to 2010, at both public and accredited private hospitals. The data are from a regional administrative database. The main epidemiological rates calculated, and expressed per 100,000 residents, were the cholecystectomy rate (CR) for gallstones by surgical technique (laparoscopic or open surgery), and the in-hospital mortality rate (MR), considered as the in-hospital MR regardless of the specific cause of death., Results: The CR was 139.7 higher in females, with a male-to-female ratio of 1:1.5. LC was performed more frequently in females than in males and in younger than in older patients. From 2001 to 2010, there was a significant linear rising trend in the use of LC, in fact during the period considered, the use of laparoscopic surgery increased significant (χ (2) trend: 316,917; p < 0.05), reaching 93.6% of surgical procedures for gallstones during the year 2010., Conclusions: There are still some age- and gender-related disparities in its usage, although LC is an increasingly widely applied, as effective procedure.
- Published
- 2013
- Full Text
- View/download PDF
34. Trend, variability, and outcome of open vs. laparoscopic appendectomy based on a large administrative database.
- Author
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Saia M, Buja A, Baldovin T, Callegaro G, Sandonà P, Mantoan D, and Baldo V
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Appendectomy statistics & numerical data, Appendectomy trends, Appendicitis epidemiology, Child, Child, Preschool, Female, Hospitalization statistics & numerical data, Humans, Infant, Italy epidemiology, Laparoscopy statistics & numerical data, Laparoscopy trends, Length of Stay, Male, Middle Aged, Retrospective Studies, Sex Distribution, Young Adult, Appendectomy methods, Appendicitis surgery, Laparoscopy methods
- Abstract
The aim of this study was to ascertain the variability and 9-year trends in the use of laparoscopic surgery for appendicitis using data from a large administrative database, to compare the effectiveness and efficiency of laparoscopic (LA) and open appendectomy, and to ascertain whether different choices of surgical approach stem from evidence-based recommendations. This was a retrospective cohort study based on administrative data collected from 2000 to 2008 in the Veneto Region (northeastern Italy). Funnel plots were used to display variability between local health units (LHUs). A total of 38,314 appendectomies were performed from 2000 to 2008 in the Veneto Region, 53% of them in males. The laparoscopic procedure was used more often for females than for males of fertile age. There was a significant rising linear trend in the use of LA, with a higher increment among females. The overall regional standardized appendectomy rate was 82.9/10,000. The mean proportion of LAs (27.3%) ranged from 2.8 to 59.4% at different LHUs, and there was no relationship between the volume of procedures undertaken and the proportion of LAs. The proportion of LAs performed in females of reproductive age also varied considerably, on no apparent evidence-based grounds. The analysis of aggregate clinical data is a powerful tool for supporting regional health management units in efforts to improve the quality of medical care and assess the appropriateness of therapeutic or diagnostic approaches in the light of practical guidelines. Variability in the treatment of a given disease that lacks any evidence-based justification remains an important issue in national health systems.
- Published
- 2012
- Full Text
- View/download PDF
35. Hospitalisation for rotavirus gastroenteritis in the paediatric population in the Veneto Region, Italy.
- Author
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Saia M, Giliberti A, Callegaro G, Baldovin T, Busana MC, Pietrobon F, Bertoncello C, and Baldo V
- Subjects
- Child, Preschool, Female, Humans, Incidence, Infant, Infant, Newborn, Italy epidemiology, Male, Patient Discharge trends, Retrospective Studies, Gastroenteritis epidemiology, Hospitalization trends, Rotavirus Infections epidemiology
- Abstract
Background: This study evaluates the epidemiological impact of RVGE hospitalisation in the Veneto Region during the period spanning from 2000-2007 along with the associated costs. The analysis was conducted in an area where rotavirus vaccination is not included into immunization programmes and is an attempt to assess the potential benefits of such introduction., Methods: To update the estimates of acute RVGE hospitalisation rates in children ≤5 years in the Veneto Region, we conducted an 8 year retrospective observational population-based analysis (2000-2007)., Results: Over the study period, a total of 4,119 admissions for RVGE were reported, with a mean hospital stay of 3.5 days. The population-based hospitalisation RVGE incidence rate was 195.8 per 100,000 children aged ≤5 years (lower than other European countries)., Conclusions: RVGE is an important cause of paediatric hospitalisation in the Veneto Region. The data reaffirm the substantial burden of rotavirus hospitalisations in children and the potential health benefits of the vaccination as well as the possibility of adding rotavirus vaccination to the current schedule.
- Published
- 2010
- Full Text
- View/download PDF
36. [Management of gastrointestinal bleeding in Veneto Region, Italy].
- Author
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Saia M, Callegaro G, Pilerci C, and Pietrobon F
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Child, Child, Preschool, Female, Gastrointestinal Hemorrhage diagnosis, Gastrointestinal Hemorrhage etiology, Gastrointestinal Hemorrhage surgery, Hospital Mortality, Humans, Incidence, Infant, Infant, Newborn, Italy epidemiology, Length of Stay statistics & numerical data, Male, Middle Aged, Retrospective Studies, Survival Rate, Gastrointestinal Hemorrhage mortality, Patient Discharge statistics & numerical data
- Abstract
Gastrointestinal bleeding (GB) is still a common medical emergency and an important cause of morbidity and mortality. There is clear evidence that early endoscopic intervention is effective in reducing mortality, length of stay and surgery procedures utilization in high-risk patients. In the last decades advances in medical practice and in endoscopic technology have influenced the management of GB, but their impact on the incidence and mortality is unclear. The aim of this study was to evaluate retrospectively time trends (2000-2007) in GB hospitalizations and in-hospital mortality, and describe the organization of endoscopic services of Veneto region, Italy. Data were collected from regional database of hospital discharge from 2000 to 2007 and all patients with an ICD 9-CM discharge diagnosis of GB were included. Overall hospitalization and in-hospital mortality rates were respectively 99.3 and 4.5 per 100.000 inh./year, the last being related to older age. Surgery procedures utilization was 5%. Hospitalization and mortality rates decreased significantly over years, probably owing to advances in the acute management of GB, principally represented by endoscopic procedures.
- Published
- 2010
37. What's in a name.
- Author
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Mariotto A, De Leo D, Realdon P, and Callegaro G
- Subjects
- Adult, Aged, Female, Humans, Male, Middle Aged, Communication, Patients, Physician-Patient Relations, Terminology as Topic
- Published
- 2001
- Full Text
- View/download PDF
38. [Somatomedin, growth and nutritional status].
- Author
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Tirapegui JO, Cardoso MA, and Callegaro Mda G
- Subjects
- Animals, Dietary Proteins pharmacology, Humans, Protein-Energy Malnutrition blood, Rats, Somatomedins physiology, Growth, Nutritional Status, Somatomedins metabolism
- Abstract
Serum somatomedins, or insulin-like growth factor(s) (IGF), originally characterized as primarily GH-dependent peptides, were found to also be dependent on insulin levels and nutritional status. Four properties characterize somatomedin peptides: their concentrations in serum are growth hormone dependent; they possess insulin actions in extraskeletal tissues; they promote the incorporation of sulfate into proteoglycans of cartilage; and they stimulate DNA synthesis and cell multiplication in certain types of cultured cells. Reduced somatomedin C levels are found in children with severe protein-energy malnutrition. Plasma concentration of growth hormone and cortisol are both elevated and there are low levels of insulin and somatomedin C. There is evidence that the ability of somatomedin C to stimulate cartilage is modulated by somatomedin inhibitor, factor that may act to limit growth in conditions of hormonal and/or nutritional deficiency. Dietary energy and protein appears to be particularly important for both generation of somatomedins and their action on growing cartilage. Measurement of somatomedins C concentration shows promise as a means for monitoring the response of malnourished patients and rats to nutrition repletion.
- Published
- 1990
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