Roberto Todeschini

Roberto Todeschini
Università degli Studi di Milano-Bicocca | UNIMIB · Department of Earth and Environmental Sciences

full professor of chemometrics

About

317
Publications
66,936
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
18,302
Citations
Citations since 2016
57 Research Items
9261 Citations
201620172018201920202021202202004006008001,0001,2001,400
201620172018201920202021202202004006008001,0001,2001,400
201620172018201920202021202202004006008001,0001,2001,400
201620172018201920202021202202004006008001,0001,2001,400
Introduction
Roberto Todeschini is full professor of chemometrics at the Department of Earth and Environmental Sciences of the University of Milano-Bicocca (Milano, Italy), where he constituted the Milano Chemometrics and QSAR Research Group. His main research activities concern chemometrics, QSAR, molecular descriptors, and software development. In particuler, in 1997 he and Viviana Consonni were the developers of the first release of DRAGON software. Member and past-president of the International Academy of Mathematical Chemistry, he is author of more than 240 publications on international journals and, together with Viviana Consonni, author of the books, “Handbook of Molecular Descriptors”, Wiley-VCH, 2000, “Molecular Descriptors for Chemoinformatics”.
Additional affiliations
Position
  • chemometrics analytical chemistry

Publications

Publications (317)
Article
The interest in multitask and deep learning strategies has been increasing in the last few years, in application to large and complex dataset for quantitative structure‐activity relationship (QSAR) analysis. Multitask approaches allow the simultaneous prediction of molecular properties that are related, through information sharing, whereas deep lea...
Article
Full-text available
The study concerns the photodegradation of the antidepressant escitalopram (ESC), the S-enantiomer of the citalopram raceme, both in ultrapure and surface water, considering the contribution of indirect photolysis through the presence of nitrate and bicarbonate. The effect of nitrate and bicarbonate concentrations was investigated by full factorial...
Article
Full-text available
Mass spectrometry (MS) is widely used for the identification of chemical compounds by matching the experimentally acquired mass spectrum against a database of reference spectra. However, this approach suffers from a limited coverage of the existing databases causing a failure in the identification of a compound not present in the database. Among th...
Article
Full-text available
Minimum Spanning Tree (MST) is a well-known clustering algorithm that provides a graphical tree representation of the objects in a data set by exploiting local information to link each pair of similar objects. The a-posteriori analysis of this tree in terms of nodes and edges provides the basis to derive simple classifiers, namely semi-supervised c...
Article
Full-text available
Neural networks are rapidly gaining popularity in chemical modeling and Quantitative Structure–Activity Relationship (QSAR) thanks to their ability to handle multitask problems. However, outcomes of neural networks depend on the tuning of several hyperparameters, whose small variations can often strongly affect their performance. Hence, optimizatio...
Article
Full-text available
Nuclear receptors (NRs) are involved in fundamental human health processes and are a relevant target for toxicological risk assessment. To help prioritize chemicals that can mimic natural hormones and be endocrine disruptors, computational models can be a useful tool.1,2 In this work we i) created an exhaustive collection of NR modulators and ii) a...
Article
Multivariate regression is a fundamental supervised chemometric approach that defines the relationship between a set of independent variables and a quantitative response. It enables the subsequent prediction of the response for future samples, thus avoiding its experimental measurement. Regression approaches have been widely applied for data analys...
Article
Full-text available
Background: Humans are exposed to tens of thousands of chemical substances that need to be assessed for their potential toxicity. Acute systemic toxicity testing serves as the basis for regulatory hazard classification, labeling, and risk management. However, it is cost- and time-prohibitive to evaluate all new and existing chemicals using traditi...
Chapter
In the analysis of complex and multivariate systems, set priorities and rank all the available objects is not a trivial task. In this framework, several multi-criteria decision-making (MCDM) techniques have been proposed, with successful applications in different research fields. However, it would be desirable to customize the ranking by weighting...
Article
Chianti is a precious red wine and enjoys a high reputation for its high quality in the world wine market. Despite this, the production region is small and product needs efficient tools to protect its brands and prevent adulterations. In this sense, ICP-MS combined with chemometrics has demonstrated its usefulness in food authentication. In this st...
Chapter
Several similarity/diversity measures for data mining, chemometrics, and chemoinformatics are presented and discussed toward the different data they are applied to. After a short presentation of the axioms for dissimilarity and similarity functions, their relationships and the required data pretreatment, the theoretical definitions and formulas of...
Article
Multi-criteria decision making processes comprehend several ranking methods able to handle multiple and often conflicting criteria and sorting objects according to a definition of the optimality direction for each criterion. In the field of polypharmacology it can be useful for virtual screening or prioritization purposes to rank molecules distingu...
Article
Full-text available
Background: Endocrine disrupting chemicals (EDCs) are xenobiotics that mimic the interaction of natural hormones and alter synthesis, transport, or metabolic pathways. The prospect of EDCs causing adverse health effects in humans and wildlife has led to the development of scientific and regulatory approaches for evaluating bioactivity. This need i...
Article
The ICCVAM Acute Toxicity Workgroup (U.S. Department of Health and Human Services), in collaboration with the U.S. Environmental Protection Agency (U.S. EPA, National Center for Computational Toxicology), coordinated the “Predictive Models for Acute Oral Systemic Toxicity” collaborative project to develop in silico models to predict acute oral syst...
Article
Ranking and multi-criteria decision-making approaches are useful tools to analyse multivariate data and obtain useful insights into data structure and the relationships between samples and variables. In this study, we present a new ranking approach, named Deep Ranking Analysis by Power Eigenvectors (DRAPE), which is based on the Power-Weakness Rati...
Article
Quantitative Structure – Activity Relationship (QSAR) models play a central role in medicinal chemistry, toxicology and computer‐assisted molecular design, as well as a support for regulatory decisions and animal testing reduction. Thus, assessing their predictive ability becomes an essential step for any prospective application. Many metrics have...
Chapter
High-level data fusion strategies combine and integrate predictions obtained by means of individual models calibrated on single information sources. With respect to other fusion techniques, high-level methods aim at improving prediction performances, as well as reducing the total uncertainty associated with the final combined outcome. In fact, when...
Article
Local classification models were used to establish quantitative structure-activity relationships (QSARs) of bioactive di-, tri- and tetrapeptides, with their capacity to inhibit Angiotensin Converting Enzyme (ACE). These discrete models can thus predict this activity for other peptides obtained from functional foods. These types of peptides allow s...
Article
Full-text available
The original PDF and HTML versions of this Article contained errors in Eqs. (4) and (6). In Eq. (4), the not equal symbol displayed incorrectly as #, and in Eq. (6), the greater than symbol was displayed in place of the less than symbol. This has been corrected in both the PDF and HTML versions of the Article.
Article
Full-text available
Natural products offer unexplored molecular frameworks for the development of chemical leads and innovative drugs. However, the structural complexity of natural products compared with synthetic drug-like molecules often limits the scaffold hopping potential of natural-product-inspired molecular design. Here we introduce a holistic molecular represe...
Conference Paper
El objetivo de este trabajo es la calibración de una relación cuantitativa estructura-actividad (QSAR) para la predicción de la actividad antiinflamatoria de alcaloides. La base de datos considerada está constituida por 100 moléculas, 52 activas y 48 inactivas. Cada estructura molecular fue modelada mediante mecánica molecular (MM+) y el método sem...
Chapter
Molecular descriptors capture diverse parts of the structural information of molecules and they are the support of many contemporary computer-assisted toxicological and chemical applications. After briefly introducing some fundamental concepts of structure–activity applications (e.g., molecular descriptor dimensionality, classical vs. fingerprint d...
Article
In the last ten years, the concept of activity cliff gained a lot of interest by medicinal chemists and QSAR modellers. The reason of this interest is its capacity to highlight problematic as well as interesting situations in analysing the activity/property of pairs of compounds, thus focusing the research on the reasons why two similar compounds s...
Article
The assessment of the classification performance can be based on class indices, such as sensitivity, specificity and precision, which describe the classification results achieved on each modelled class. However, in several situations, it is useful to represent the global classification performance with a single number. Therefore, several measures h...
Article
A new chemoinformatic approach, called Mapping of Activity through Dichotomic Scores, is introduced. Its goal is the supervised projection of molecules, represented with strings of binary digits expressing the presence or absence of selected structural features, onto a novel 2-dimensional space, which highlights regions of active (inactive) molecul...
Chapter
Molecular descriptors encode a wide variety of molecular information and have become the support of many contemporary chemoinformatic and bioinformatic applications. They grasp specific molecular features (e.g., geometry, shape, pharmacophores, or atomic properties) and directly affect computational models, in terms of outcome, performance, and app...
Article
REACH requires that all chemicals produced or imported for more than 1 ton/year must be tested for ready biodegradability, a screening test for the assessment of chemical persistence. Since REACH encourages the use of in-silico approaches, several Quantitative Structure-Activity Relationship models have been calibrated to predict this property. Pre...
Article
Full-text available
This work describes a novel approach based on advanced molecular similarity to predict the sweetness of chemicals. The proposed Quantitative Structure-Taste Relationship (QSTR) model is an expert system developed keeping in mind the five principles defined by the Organization for Economic Co-operation and Development for the validation of (Q)SARs....
Article
Atmospheric pollutants can originate the decay of historic paintings exposed to the outdoor elements. This is a cause of great concern, since such contaminants can produce physical-chemical alterations manifested initially in undesirable color change. This paper tests an unsupervised multivariate approach on discrete data color parameters in a pion...
Article
Full-text available
There is an increasing necessity for multidisciplinary collaborations in molecular science between experimentalists and theoretical scientists, as well as among theoretical scientists from different fields. One of the more important forces driving this necessity is the accumulation of large amounts of data as a result of important advances in Chemi...
Article
Full-text available
This communication deals with the scientific problem of evaluating the similarity between two chemical systems, each described by a finite discrete set of elements/members, which are in turn p-dimensional vectors of chemical/biological descriptors. A variant of the Hausdorff measure, called Hausdorff-like similarity (Hs), is proposed aimed at takin...
Poster
Full-text available
The aim of this work was the development of an expert system model based on quantitative structure-taste relationships (QSTRs) to predict the sweetness of molecules. Molecules were described by extended connectivity fingerprints (ECFPs) and conformation-independent molecular descriptors (MDs).
Poster
Full-text available
El objetivo de este trabajo fue el desarrollo de dos modelos preliminares basados en las relaciones cuantitativas estructura-actividad (QSARs), usando los métodos de clasificación N3 y PLSDA, para clasificar moléculas dulces y no dulces.
Poster
Full-text available
En este trabajo se presenta el desarrollo de una relación cuantitativa estructura-actividad basado en el nuevo método de clasificación de los N-vecinos (QSAR-N3) para péptidos bioactivos (PBA) con capacidad de inhibir enzima convertidora de la angiotensina (ACE)
Article
Molecular descriptors capture diverse structural information of molecules and are a prerequisite for ligand-based similarity searching. In this study, we introduce topological matrix-based descriptors to virtual screening for hit discovery. We evaluated the usefulness of matrix-based descriptors in a retrospective setting and compared them with top...
Article
Validation is an essential step of QSAR modelling and it can be performed by both internal validation techniques (e.g. cross-validation, bootstrap) or by an external set of test objects, that is, objects not used for model development and/or optimisation. The evaluation of model predictive ability is then established comparing experimental and pred...
Article
Full-text available
Cytochromes P450 (CYP) are the main actors in the oxidation of xenotibiotics and play a crucial role in drug safety, persistence, bioactivation, and drug-drug/food-drug interaction. This work aims to develop Quantitative Structure-Activity Relationship (QSAR) models to predict the drug interaction with two of the most important CYP isoforms, namely...
Article
In this paper, a new concept of similarity is introduced with the aim of detecting higher-order similarities among objects and meta-distances and meta-similarities are derived from it. A total of 100 meta-distances were obtained from a set of ten classical distances and were compared, in terms of classification performances, against classical dista...
Book
A systematic guide to the growing jungle of citation indices and other bibliometric indicators. Written with the aim of providing a complete and unbiased overview of all available statistical measures for scientific productivity, the core of this reference is an alphabetical dictionary of indices and other algorithms used to evaluate the importance...
Conference Paper
Full-text available
Keywords: paint dosimeter; natural aging test; portable spectrophotometer; PCA; Decay of outdoor paint artworks due to polluted urban atmospheres is an outstanding problem with paramount cultural and economic consequences that is attracting the attention of researchers in the last decades [1][2]. In this context, evaluation of the effects of urban...
Conference Paper
Full-text available
Keywords: paint mock-ups, UV artificial ageing test; MALDI-TOF-MS; micro-Raman spectroscopy; portable spectrophotometer; similarity index. Degradation and darkening of outdoor paintings exposed to polluted and coastal urban atmosphere is acquiring significance due to new atmospheric contaminants and the effects of climate change. This problem is en...
Article
Full-text available
This paper proposes a scheme to predict whether a compound (1) is mainly stored within lipid tissues, (2) has additional storage sites (e.g., proteins), or (3) is metabolized/eliminated with a reduced bioconcentration. The approach is based on two validated QSAR (Quantitative-Structure Activity Relationship) trees, whose salient features are: (a) d...
Article
Full-text available
Similarity searching, a technique used for ligand-based virtual screening in drug discovery, exploits the structural information of known active compounds to find new ones with the desired biological activity. The effectiveness of similarity searching can be enhanced by combining independent searches, executed with different reference structures, t...
Article
Full-text available
The aim of this work was the calibration and validation of mathematical models based on a quantitative structure–activity relationship approach to discriminate sweet, tasteless and bitter molecules. The sweet-tasteless and the sweet-bitter datasets included 566 and 508 compounds, respectively. A total of 3763 conformation-independent Dragon molecul...
Article
Full-text available
Background: Humans are exposed to thousands of man-made chemicals in the environment. Some chemicals mimic natural endocrine hormones and, thus, have the potential to be endocrine disruptors. Most of these chemicals have never been tested for their ability to interact with the estrogen receptor (ER). Risk assessors need tools to prioritize chemica...
Article
Two novel classification methods, called N3 (N-Nearest Neighbours) and BNN (Binned Nearest Neighbours), are proposed. Both methods are inspired by the principles of the K-Nearest Neighbours (KNN) method, being both based on object pairwise similarities. Their performance was evaluated in comparison with nine well-known classification methods. In or...
Article
This work presents a modified version of Hasse Diagram technique, the weighted Regularized Hasse (wR-Hasse), which aims to reduce the number of incomparabilities and derive weighted rankings of the objects. These objectives are accomplished by: (a) introducing a mathematical threshold on the definition of incomparability and (b) weighting criteria...
Poster
Full-text available
Congress of Theoretical Chemists of Latin Expression. Turin, Italy. 26-31 July
Article
Full-text available
REACH regulation demands information about acute toxicity of chemicals towards fish and supports the use of QSAR models, provided compliance with OECD principles. Existing models present some drawbacks that may limit their regulatory application. In this study, a dataset of 908 chemicals was used to develop a QSAR model to predict the LC50 96 hours...
Chapter
Several similarity/diversity measures for data mining and chemometrics are presented and discussed toward the different data they are applied to. After a short presentation of the axioms for dissimilarity and similarity functions, their relationships, and the required data pretreatment, the theoretical definitions and formulas of distance and simil...
Article
A series of 436 Munro database chemicals were studied with respect to their corresponding experimental LD50 values to investigate the possibility of establishing a global QSAR model for acute toxicity. Dragon molecular descriptors were used for the QSAR model development and genetic algorithms were used to select descriptors better correlated with...