67 results on '"Mignani S"'
Search Results
2. Contrast-enhanced US and MRI for assessing the response of breast cancer to neoadjuvant chemotherapy
- Author
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Corcioni, B., Santilli, L., Quercia, S., Zamagni, C., Santini, D., Taffurelli, M., and Mignani, S.
- Published
- 2008
- Full Text
- View/download PDF
3. A promising dual mode SPECT/CT imaging platform based on 99mTc-labeled multifunctional dendrimer-entrapped gold nanoparticles
- Author
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Wen, S, Zhao, L, Zhao, Q, Li, D, Liu, C, Yu, Z, Shen, M, Majoral, JP, Mignani, S, Zhao, J, and Shi, X
- Abstract
© 2017 The Royal Society of Chemistry. Multifunctional 99mTc-labeled dendrimer-entrapped gold nanoparticles (99mTc-Au DENPs) were designed and synthesized. Our results show that the type of surface groups (acetyl or hydroxyl) significantly impact the biodistribution profile of the 99mTc-Au DENPs, thereby allowing for preferential SPECT/CT imaging of different organs.
- Published
- 2017
4. A comparison between latent variable models for evaluating the quality perceived from the hospital service users
- Author
-
Cagnone, S., Cavrini, G., and Mignani, S.
- Subjects
lcsh:Statistics ,lcsh:HA1-4737 - Abstract
During the last years, costumer satisfaction analysis is becoming more and more important in evaluating the service quality of the sanitary system. Typically the construct ‘satisfaction’ is assumed to be a not observable variable, that is a latent variable. In this paper we illustrate and compare two different methods for analyzing latent variable models. The first one is the structural equation models with Lisrel, the second one is the generalized linear latent variable models. The comparison is performed through an application of the satisfaction analysis to a real data set referred to the patients of a hospital in Bologna. The results highlights the methodological and the applicative similarity and dissimilarity between the two methods., Statistica; Vol 64, No 4 (2004); 655-672
- Published
- 2007
5. Construction of polydopamine-coated gold nanostars for CT imaging and enhanced photothermal therapy of tumors: an innovative theranostic strategy.
- Author
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Li, D, Zhang, Y, Wen, S, Song, Y, Tang, Y, Zhu, X, Shen, M, Mignani, S, Majoral, J-P, Zhao, Q, Shi, X, Li, D, Zhang, Y, Wen, S, Song, Y, Tang, Y, Zhu, X, Shen, M, Mignani, S, Majoral, J-P, Zhao, Q, and Shi, X
- Abstract
The advancement of biocompatible nanoplatforms with dual functionalities of diagnosis and therapeutics has been strongly demanded in biomedicine in recent years. In this work, we report the synthesis and characterization of polydopamine (pD)-coated gold nanostars (Au NSs) for computed tomography (CT) imaging and enhanced photothermal therapy (PTT) of tumors. Au NSs were firstly formed via a seed-mediated growth method and then stabilized with thiolated polyethyleneimine (PEI-SH), followed by deposition of pD on their surface. The formed pD-coated Au NSs (Au-PEI@pD NSs) were well characterized. We show that the Au-PEI@pD NSs are able to convert the absorbed near-infrared laser light into heat, and have strong X-ray attenuation properties. Due to the co-existence of Au NSs and pD, the light to heat conversion efficiency of the NSs can be significantly enhanced. These very interesting properties allow them to be used as a powerful theranostic nanoplatform for efficient CT imaging and enhanced phtotothermal therapy of cancer cells in vitro and the xenografted tumor model in vivo. Due to their easy functionalization nature enabled by the coated pD shell, the developed pD-coated Au NSs may be used as a versatile nanoplatform for targeted CT imaging and PTT of different types of cancers.
- Published
- 2016
6. Model selection procedures in three-mode component models
- Author
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Kroonenberg, P.M., Vichi, M., Molinari, P., Mignani, S., and Montanari, A.
- Published
- 2005
7. A Family of Indices for Teaching Evaluation: Experiences in Italian Universities
- Author
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Crescenzi, F, Mignani, S, Marasini, D, Quatto, P, MARASINI, DONATA, QUATTO, PIERO, Crescenzi, F, Mignani, S, Marasini, D, Quatto, P, MARASINI, DONATA, and QUATTO, PIERO
- Abstract
In order to analyze the student ratings of University teaching, several indices summarize the relative frequencies of positive and negative responses in a single numerical value. Focusing on linear functions of response frequencies, the paper studies some interesting families of indices for the measurement of student satisfaction. Special attention is paid to relationships between these families and to a particular family that arises in a natural way.
- Published
- 2014
8. Fifty Years of Business Confidence Surveys on Manufacturing Sector
- Author
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Crescenzi, F, Mignani, S, Martelli, B, Bruno, G, Chiodini, P, Manzi, G, Verrecchia, F, Martelli, BM, Chiodini, PM, Crescenzi, F, Mignani, S, Martelli, B, Bruno, G, Chiodini, P, Manzi, G, Verrecchia, F, Martelli, BM, and Chiodini, PM
- Abstract
In this work the evolution of the Italian Business Confidence Survey on manufacturing sector is presented starting from the preliminary European project for harmonized statistics launched in the late fifties of the last century. Survey changes are described, focusing in particular on the so-called confidence indicator. The continuing increase of statistical accuracy in sampling is recalled, from the initial purposive sample and controls, up to the present state of the art. Specific attention is devoted to the role of administrative archives in the sampling plan. Emphasis is also given to the increasing use of computer simulation in assessing the validity of the estimates. The role of cyclical analysis is finally highlighted with regard to two aspects: (1) the business confidence has not a corresponding variable in the economic system—the validation can only be performed in comparison with correlated variables (e.g. IP, GDP); (2) confidence shows forecasting capability for the economic system.
- Published
- 2014
9. A New Version of the Structural Dynamic Model with Unique Latent Scores
- Author
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Bock, HH, Gaul, W, Vichi, M, Arabie, P, Baier, D, Critchley, F, Decker, R, Diday, E, Greenacre, M, Lauro, C, Meulman, J, Monari, P, Nishisato, S, Ohsumi, N, Opitz, O, Ritter, G, Schader, M, Weihs, C, Mignani, S, Montanari, A, Minotti, S, Vittadini, G, MINOTTI, SIMONA CATERINA, VITTADINI, GIORGIO, Bock, HH, Gaul, W, Vichi, M, Arabie, P, Baier, D, Critchley, F, Decker, R, Diday, E, Greenacre, M, Lauro, C, Meulman, J, Monari, P, Nishisato, S, Ohsumi, N, Opitz, O, Ritter, G, Schader, M, Weihs, C, Mignani, S, Montanari, A, Minotti, S, Vittadini, G, MINOTTI, SIMONA CATERINA, and VITTADINI, GIORGIO
- Abstract
The indeterminacy of the Structural Models, i.e. the arbitrariness of latent scores, due to the factorial nature of the measurement models, is, in the dynamic context, more problematic. We propose an alternative formulation of the Structural Dynamic Model, based on the Replicated Common Factor Model (Haagen e Oberhofer, 1999), where latent scores are no more indeterminate.
- Published
- 2005
10. Selection of Structural Equation Models with the Pls.VB Programme
- Author
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Vichi, M, Mignani, S, Monari, P, Montanari A, Boari, Giuseppe, Cantaluppi, Gabriele, Boari, Giuseppe (ORCID:0000-0002-3208-2771), Cantaluppi, Gabriele (ORCID:0000-0001-5234-3900), Vichi, M, Mignani, S, Monari, P, Montanari A, Boari, Giuseppe, Cantaluppi, Gabriele, Boari, Giuseppe (ORCID:0000-0002-3208-2771), and Cantaluppi, Gabriele (ORCID:0000-0001-5234-3900)
- Published
- 2005
11. On the Electronic-structure of Captodative Substituted Olefins
- Author
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UCL, Sustmann, R., Muller, W., Mignani, S., Merenyi, R., Janousek, Z., Viehe, HG., UCL, Sustmann, R., Muller, W., Mignani, S., Merenyi, R., Janousek, Z., and Viehe, HG.
- Published
- 1989
12. Captodative Substituent Effects .49. Esr Study of Carbon Centered Transient Radicals Using Alpha-tert-butylthioacrylonitrile As Radical Trap
- Author
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UCL, Merenyi, R., Janousek, Z., Viehe, HG., Mignani, S., UCL, Merenyi, R., Janousek, Z., Viehe, HG., and Mignani, S.
- Published
- 1989
13. [A Model for Oxygenated-radical Trapping - Captodative-olefin Trapping of T-butoxy Radicals]
- Author
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UCL, Gorissenhervens, F., Mignani, S., Janousek, Z., Merenyi, R., Viehe, HG., UCL, Gorissenhervens, F., Mignani, S., Janousek, Z., Merenyi, R., and Viehe, HG.
- Published
- 1986
14. [Captodative Stabilization .20. Addition of Nucleophilic Radicals Derived From Alkanes, Ethers, Thioethers, Amides, Amines, Alcohols, Ketals and Thioketals To Alpha-tertiary Butylthioacrylonitrile]
- Author
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UCL, Mignani, S., Janousek, Z., Merenyi, R., Viehe, HG., UCL, Mignani, S., Janousek, Z., Merenyi, R., and Viehe, HG.
- Published
- 1985
15. [Couplage okydatif facile d'anions substitues captodativement]
- Author
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UCL, Mignani, S., Lahousse, F., Merenyi, R., Janousek, Z., Viehe, HG., UCL, Mignani, S., Lahousse, F., Merenyi, R., Janousek, Z., and Viehe, HG.
- Published
- 1985
16. X-ray Photoelectron Spectroscopic Study of Captodative Olefins - Electronic-structure of Alpha-thio-acrylonitrile Derivatives
- Author
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UCL, Riga, Joseph, Verbist, JJ., Mignani, S., Janousek, Z., Merenyi, R., Viehe, HG., UCL, Riga, Joseph, Verbist, JJ., Mignani, S., Janousek, Z., Merenyi, R., and Viehe, HG.
- Published
- 1985
17. Captodative Substituent Effects .22. Radical Dehydrodimerisation and Bridged Dehydrodimerisation of Macrocyclic Polyethers
- Author
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UCL, Beaujean, M., Mignani, S., Merenyi, R., Janousek, Z., Viehe, HG., Kirch, M., Lehn, JM., UCL, Beaujean, M., Mignani, S., Merenyi, R., Janousek, Z., Viehe, HG., Kirch, M., and Lehn, JM.
- Published
- 1984
18. Bridged Dehydrodimerisation .3. Preparative Trapping of Tert-butoxy Radicals By Captodative Olefins
- Author
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UCL, Mignani, S., Janousek, Z., Merenyi, R., Viehe, HG., Riga, Joseph, Verbist, J., UCL, Mignani, S., Janousek, Z., Merenyi, R., Viehe, HG., Riga, Joseph, and Verbist, J.
- Published
- 1984
19. Capto-dative Substituent Effects .8. Bridged Dehydrodimerization As a General-method of Synthesis - C-4-bridging With Alpha-tert-butylmer-captoacrylonitrile
- Author
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UCL, Mignani, S., Beaujean, M., Janousek, Z., Merenyi, R., Viehe, HG., UCL, Mignani, S., Beaujean, M., Janousek, Z., Merenyi, R., and Viehe, HG.
- Published
- 1981
20. 3,4-Functionalized silacyclopentanes. Synthesis of trans-4-amino-, azido- and alkyloxy-1-silacyclopentan-3-ols from 6-oxa-3-silabicyclo[3,1,0]hexanes
- Author
-
Boukherroub, R., Manuel, G., Mignani, S., and Damour, D.
- Published
- 1994
- Full Text
- View/download PDF
21. A propensity score matching method to study the achievement of students in upper secondary schools
- Author
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Giulia Roli, Luisa Stracqualursi, Fabio Crescenzi, Stefania Mignani, Roli G., Stracqualursi L., and MIGNANI S., COSTA M.
- Subjects
Matching (statistics) ,education ,Average treatment effect ,Outcome (probability) ,Educational attainment ,Treatment and control groups ,Causal inference ,Covariate ,Propensity score matching ,Statistics ,Mathematics education ,causal inference ,Psychology ,student achievement ,propensity score - Abstract
In the paper, the achievement of students in the first year of the upper sec- ondary schools of the province of Bologna is investigated. In particular, we focus our attention on school location as potential causal factor influencing the outcome by comparing students from urban area schools with those from other towns of the province. We show that valid inference is assured by controlling for family back- ground whose influence on the outcome has been previously assessed.We employ a matching strategy based on propensity score to create treatment groups, correspond- ing to the values of the factor under study, with the same distribution of observed covariates. As a result, students are stratified in blocks according to the propensity score to obtain estimates of the average treatment effect using nearest neighbour matching. The role of family characteristics is further studied by testing whether the effect of school location on student achievements depends on number of siblings and educational qualification of the mother.
- Published
- 2014
22. A distributional approach for measuring wage discrimination and occupational discrimination separately
- Author
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GIAIMO, Rosa, LO MAGNO, Giovanni Luca, Giaimo, R, Lo Magno, GL, Mignani, S, Crescenzi, F, and Lo Magno GL
- Subjects
Settore SECS-S/02 - Statistica Per La Ricerca Sperimentale E Tecnologica ,gender issue ,segregation ,wage discrimination, occupational discrimination, segregation ,Wage discrimination, distributional approach ,wage discrimination - Abstract
Numerous statistical methodologies regarding the study of discrimination are based on the well-known Blinder-Oaxaca (1973) decomposition. This divides the wage differential between men and women into one part, which can be explained by differences in individual characteristics, and another part, which is interpreted as discrimination. This decomposition ignores any distributional issues in evaluating discrimination, thus permitting, undesirably, compensation between positively and negatively discriminated women. Jenkins (1994) has criticized this aspect, instead preferring a distributional approach. Del Rio et al. (2010), using a distributional approach, which hinges on the deprivational aspect of discrimination, adapts the Foster-Greer-Thorbecke (1984) class of poverty indices to the study of discrimination. Studies adopting the distributional approach pay little attention to the issue of the separate measuring of wage discrimination and occupational discrimination. Instead, our Paper uses the Foster-Greer-Thorbecke indices for measuring wage discrimination and occupational discrimination separately. Similar to the technique employed in the Brown-Moon-Zoloth decomposition (1980), we have thus used a multinomial model to estimate the theoretical distribution of women in occupation, in the absence of occupational discrimination.
- Published
- 2011
23. CONTRAST- ENHANCEMENT US AND MRI FOR ASSESSING THE RESPONSE OF BREAST CANCER TO NEOADJUVANT CHEMOTHERAPY
- Author
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B. Corcioni, Stefano Mignani, Claudio Zamagni, Mario Taffurelli, Sara Quercia, Donatella Santini, L. Santilli, Corcioni B, Santilli L, Quercia S, Zamagni C, Santini D, Taffurelli M, and Mignani S.
- Subjects
Pathology ,medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Ultrasound ,Magnetic resonance imaging ,General Medicine ,medicine.disease ,Malignancy ,Article ,Surgical pathology ,breast ultrasonography ,Breast cancer ,Contrast-enhanced US ,BREAST CANCER ,Biopsy ,Internal Medicine ,medicine ,Mammography ,Radiology, Nuclear Medicine and imaging ,business ,Nuclear medicine ,Breast carcinoma - Abstract
To evaluate the response of breast cancers to neoadjuvant chemotherapy (NAC) with second-generation contrast-enhanced ultrasound (CEUS) and magnetic resonance (MR).We studied 16 women aged 33-74 years (mean, 53 years; median, 38 years) with locally advanced breast carcinoma or large operable breast cancer (2 cm; T2-T4, N0-N3, M0) that had been detected by mammography, conventional ultrasonography, and biopsy. CEUS (with SonoVue, 5 ml) and MR (with Gd-DTPA; 0.2 mM/kg) were performed under blinded conditions before, during, and after 6-8 cycles of NAC. Lesions were measured and time/signal intensity (T/SI) curves were calculated during both the examinations. The data obtained were analyzed in light of the results of surgical pathology.Six patients had complete responses manifested by the disappearance of enhancement at both CEUS and MR. Six others had partial responses (reduction of lesion enhancement50%). In 5/6, T/SI curves obtained with CEUS and MR were both indicative of malignancy (flat curves at CEUS, type I curves at MR); the sixth had a discontinuous curve at CEUS and a type II curve at MR. Four patients had lesional enhancement reductions of50%. In 3, concordant pictures emerged from the analysis of T/SI curves (discontinuous curves in CEUS, type II and III curves in MR); the fourth had a flat CEUS curve and a type I MR curve. Responses to NAC classified on the basis of MR and CEUS findings showed good correlation with the pathological response.T/SI curves recorded during CEUS correlate with those obtained during MR and may be a valid index of response to the therapy.Sommario SCOPO: Valutare la risposta alla chemioterapia neoadiuvante (NAC) in pazienti con carcinoma della mammella confrontando l'ecografia con mezzo di contrasto di seconda generazione (CEUS) con la risonanza magnetica (RM). MATERIALI E METODI: Sedici pazienti (età fra 33 e 74 anni; media di 53 anni; mediana 38 anni) affette da carcinoma mammario localmente avanzato o operabile ma superiore a 2 cm (T2-T4; N0-N3; M0), già diagnosticato con mammografia, ecografia convenzionale e biopsia, sono state monitorate con CEUS (con SonoVue, 5 ml) e RM (con Gd-DTPA, 0,2 mM/kg). Le indagini sono state effettuate in cieco: prima di iniziare il trattamento, dopo 4 cicli di terapia e prima dell'intervento chirurgico. Con entrambe le metodiche sono state calcolate le dimensioni delle lesioni e le curve tempo/intensità di segnale (T/IS). I dati ottenuti sono stati confrontati con l'esame patologico eseguito al termine della terapia sul pezzo operatorio. RISULTATI: Sei su 16 pazienti hanno mostrato sia alla CEUS sia alla RM una risposta completa alla NAC con scomparsa di enhancement. In 6 su 16 pazienti si è riscontrata una riduzione parziale dell'enhancement delle lesioni (50%) con curve T/IS concordanti fra CEUS e RM in cinque casi (in particolare curve piatte alla CEUS e di tipo I alla RM); nel sesto caso la curva è stata di tipo indeterminato sia alla CEUS sia alla RM. Quattro su 16 pazienti hanno presentato una riduzione dell'enhancement delle lesioni50% con curve T/IS concordanti in tre casi (curve irregolari alla CEUS e di tipo II e III alla RM); nel quarto caso la curva è stata piatta alla CEUS e di tipo I alla RM. Si è osservata una buona corrispondenza fra la risposta al trattamento valutata con CEUS e RM e quella patologica. CONCLUSIONI: I risultati ottenuti dimostrano che le curve T/IS della CEUS correlano con quelle calcolate con RM e sembrano essere un valido indice di risposta alla terapia.
- Published
- 2008
24. Var Models for Spatio-Temporal Structures: an application to environmental data
- Author
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Alessia Naccarato, A. Lamberti, AA VV, Vichi M, Monari P, Mignani S, Montanari A, Lamberti, A, Naccarato, Alessia, and Lamberti, A.
- Subjects
Meteorology ,Autoregressive model ,Single site ,Sunshine duration ,Environmental science ,Mediterranean Basin ,Intensity (heat transfer) ,Environmental data - Abstract
In this work we propose the use of Vector Autoregressive Models (ST-VAR) and Generalized Vector Autoregressive Models (ST-GVAR) for spatio-temporal data in which relations among different sites of a monitoring network are not exclusively dependent on the distance among them but take also into account intensity and direction that a phenomenon measured on the whole network has on a single site of the network. We present an application of these models using data of fifteen italian meteorological locations of Mediterranean Basin.
- Published
- 2005
25. Selecting the training set in classification problems with rare events
- Author
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Bruno Scarpa, Nicola Torelli, Scarpa, B, Torelli, Nicola, VICHI M, MONARI P., MIGNANI S., MONTANARI A., and Scarpa, B.
- Subjects
Boosting (machine learning) ,Training set ,business.industry ,Computer science ,Decision tree learning ,logistic regression ,Pattern recognition ,balancing ,Machine learning ,computer.software_genre ,Statistical classification ,ComputingMethodologies_PATTERNRECOGNITION ,Binary classification ,classification tree ,Rare events ,Artificial intelligence ,business ,computer - Abstract
Binary classification algorithms are often used in situations when one of the two classes is extremely rare. A common practice is to oversample units of the rare class when forming the training set. For some classification algorithms, like logistic classification, there are theoretical results that justify such an approach. Similar results are not available for other popular classification algorithms like classification trees. In this paper the use of balanced datasets, when dealing with rare classes, for tree classifiers and boosting algorithms is discussed and results from analyzing a real dataset and a simulated dataset are reported.
- Published
- 2003
26. A different approach for the analysis of web access logs
- Author
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Giuseppe Melfi, Gabriella Schoier, VICHI M., MONARI P., MIGNANI S., MONTANARI A., Schoier, Gabriella, and Melfi, G.
- Subjects
web usage mining ,web access logs ,social network analysis ,Computer science ,business.industry ,Social network analysis (criminology) ,Web access ,Personalization ,World Wide Web ,Identification (information) ,web access log ,The Internet ,business - Abstract
The development of Internet-based business has pointed out the importance of the personalisation and optimisation of Web sites. For this purpose the study of users behaviours are of great importance. In this paper we present a solution to the problem of identification of dense clusters in the analysis of Web Access Logs. We consider a modification of an algorithm recently proposed in social network analysis. This approach is illustrated by analysing a log-file of a web portal.
27. Bioactive phosphorus dendrimers deliver protein/drug to tackle osteoarthritis via cooperative macrophage reprogramming.
- Author
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Sun H, Zhan M, Zou Y, Ma J, Liang J, Tang G, Laurent R, Mignani S, Majoral JP, Shi X, and Shen M
- Subjects
- Animals, Mice, Humans, Quercetin pharmacology, Quercetin therapeutic use, Quercetin administration & dosage, Catalase metabolism, RAW 264.7 Cells, Male, Cellular Reprogramming drug effects, Drug Delivery Systems, Mice, Inbred C57BL, Mesenchymal Stem Cells drug effects, Mesenchymal Stem Cells metabolism, Mesenchymal Stem Cells cytology, Oxidative Stress drug effects, Osteoarthritis pathology, Osteoarthritis drug therapy, Macrophages drug effects, Macrophages metabolism, Dendrimers chemistry, Dendrimers pharmacology, Phosphorus chemistry
- Abstract
Reprogramming imbalanced synovial macrophages and shaping an immune microenvironment conducive to bone and cartilage growth is crucial for efficient tackling of osteoarthritis (OA). Herein, we present a co-delivery nanosystem based on generation 2 (G2) hydroxyl-terminated bioactive phosphorus dendrimers (G2-OH
24 ) that were loaded with both catalase (CAT) and quercetin (Que). The created G2-OH24 /CAT@Que complexes exhibit a uniformly distributed spherical morphology with a size of 138.8 nm, possess robust stability, and induce macrophage reprogramming toward anti-inflammatory M2 phenotype polarization and antioxidation through cooperative CAT-catalyzed oxygen generation, Que-mediated mitochondrial homeostasis restoration, and inherent immunomodulatory activity of dendrimer. Such macrophage reprogramming leads to chondrocyte apoptosis inhibition and osteogenic differentiation of bone mesenchymal stem cells. Administration of G2-OH24 /CAT@Que to an OA mouse model results in attenuation of pathological features such as cartilage degeneration, bone erosion, and synovitis through oxidative stress alleviation and inflammatory factor downregulation in inflamed joints. Excitingly, the G2-OH24 /CAT@Que also polarized macrophages in adherent effusion monocytes (AEMs) extracted from joint cavity effusions of OA patients to M2 phenotype and downregulated reactive oxygen species levels in AEMs. This study suggests a promising nanomedicine formulation of phosphorus dendrimer-based co-delivery system to effectively tackle OA through the benefits of full-active ingredients of dendrimer, drug, and protein., 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 © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2025
- Full Text
- View/download PDF
28. Brain delivery of fibronectin through bioactive phosphorous dendrimers for Parkinson's disease treatment via cooperative modulation of microglia.
- Author
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Dai W, Zhan M, Gao Y, Sun H, Zou Y, Laurent R, Mignani S, Majoral JP, Shen M, and Shi X
- Abstract
Effective treatment of Parkinson's disease (PD), a prevalent central neurodegenerative disorder particularly affecting the elderly population, still remains a huge challenge. We present here a novel nanomedicine formulation based on bioactive hydroxyl-terminated phosphorous dendrimers (termed as AK123) complexed with fibronectin (FN) with anti-inflammatory and antioxidative activities. The created optimized AK123/FN nanocomplexes (NCs) with a size of 223 nm display good colloidal stability in aqueous solution and can be specifically taken up by microglia through FN-mediated targeting. We show that the AK123/FN NCs are able to consume excessive reactive oxygen species, promote microglia M2 polarization and inhibit the nuclear factor-kappa B signaling pathway to downregulate inflammatory factors. With the abundant dendrimer surface hydroxyl terminal groups, the developed NCs are able to cross blood-brain barrier (BBB) to exert targeted therapy of a PD mouse model through the AK123-mediated anti-inflammation for M2 polarization of microglia and FN-mediated antioxidant and anti-inflammatory effects, thus reducing the aggregation of α-synuclein and restoring the contents of dopamine and tyrosine hydroxylase to normal levels in vivo . The developed dendrimer/FN NCs combine the advantages of BBB-crossing hydroxyl-terminated bioactive per se phosphorus dendrimers and FN, which is expected to be extended for the treatment of different neurodegenerative diseases., Competing Interests: 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., (© 2024 The Authors.)
- Published
- 2024
- Full Text
- View/download PDF
29. Polycationic phosphorous dendrimer potentiates multiple antibiotics against drug-resistant mycobacterial pathogens.
- Author
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Imran M, Singh S, Ahmad MN, Malik P, Mukhopadhyay A, Yadav KS, Gupta UD, Mugale MN, Mitra K, Srivastava KK, Chopra S, Mignani S, Apartsin E, Majoral JP, and Dasgupta A
- Subjects
- Animals, Mice, Anti-Bacterial Agents pharmacology, Pharmaceutical Preparations, Dendrimers pharmacology, Tuberculosis microbiology, Mycobacterium tuberculosis
- Abstract
Mycobacterium tuberculosis (Mtb), causative agent of tuberculosis (TB) and non-tubercular mycobacterial (NTM) pathogens such as Mycobacterium abscessus are one of the most critical concerns worldwide due to increased drug-resistance resulting in increased morbidity and mortality. Therefore, focusing on developing novel therapeutics to minimize the treatment period and reducing the burden of drug-resistant Mtb and NTM infections are an urgent and pressing need. In our previous study, we identified anti-mycobacterial activity of orally bioavailable, non-cytotoxic, polycationic phosphorus dendrimer 2G0 against Mtb. In this study, we report ability of 2G0 to potentiate activity of multiple classes of antibiotics against drug-resistant mycobacterial strains. The observed synergy was confirmed using time-kill kinetics and revealed significantly potent activity of the combinations as compared to individual drugs alone. More importantly, no re-growth was observed in any tested combination. The identified combinations were further confirmed in intra-cellular killing assay as well as murine model of NTM infection, where 2G0 potentiated the activity of all tested antibiotics significantly better than individual drugs. Taken together, this nanoparticle with intrinsic antimycobacterial properties has the potential to represents an alternate drug candidate and/or a novel delivery agent for antibiotics of choice for enhancing the treatment of drug-resistant mycobacterial pathogens., 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 © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
30. Synthesis and interest in medicinal chemistry of β-phenylalanine derivatives (β-PAD): an update (2010-2022).
- Author
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Rémondin C, Mignani S, Rochais C, and Dallemagne P
- Subjects
- Humans, Molecular Structure, Drug Discovery, Phenylalanine chemistry, Phenylalanine chemical synthesis, Phenylalanine analogs & derivatives, Chemistry, Pharmaceutical
- Abstract
β-Phenylalanine derivatives (β-PAD) represent a structural family of therapeutic interest, either as components of drugs or as starting materials for access to key compounds. As scaffolds for medicinal chemistry work, β-PAD offer the advantage of great diversity and modularity, a chiral pseudopeptidic character that opens up the capacity to be recognized by natural systems, and greater stability than natural α-amino acids. Nevertheless, their synthesis remains a challenge in drug discovery and numerous methods have been devoted to their preparation. This review is an update of the access routes to β-PAD and their various therapeutic applications.
- Published
- 2024
- Full Text
- View/download PDF
31. Antipsychotics: 70 Years.
- Author
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Lentini G and Mignani S
- Abstract
To Davide [...] .
- Published
- 2023
- Full Text
- View/download PDF
32. Endocannabinoid Degradation Enzyme Inhibitors as Potential Antipsychotics: A Medicinal Chemistry Perspective.
- Author
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Mangiatordi GF, Cavalluzzi MM, Delre P, Lamanna G, Lumuscio MC, Saviano M, Majoral JP, Mignani S, Duranti A, and Lentini G
- Abstract
The endocannabinoid system (ECS) plays a very important role in numerous physiological and pharmacological processes, such as those related to the central nervous system (CNS), including learning, memory, emotional processing, as well pain control, inflammatory and immune response, and as a biomarker in certain psychiatric disorders. Unfortunately, the half-life of the natural ligands responsible for these effects is very short. This perspective describes the potential role of the inhibitors of the enzymes fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MGL), which are mainly responsible for the degradation of endogenous ligands in psychic disorders and related pathologies. The examination was carried out considering both the impact that the classical exogenous ligands such as Δ
9 -tetrahydrocannabinol (THC) and (-)-trans-cannabidiol (CBD) have on the ECS and through an analysis focused on the possibility of predicting the potential toxicity of the inhibitors before they are subjected to clinical studies. In particular, cardiotoxicity (hERG liability), probably the worst early adverse reaction studied during clinical studies focused on acute toxicity, was predicted, and some of the most used and robust metrics available were considered to select which of the analyzed compounds could be repositioned as possible oral antipsychotics.- Published
- 2023
- Full Text
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33. Modulation of Macrophages Using Nanoformulations with Curcumin to Treat Inflammatory Diseases: A Concise Review.
- Author
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Sun H, Zhan M, Mignani S, Shcharbin D, Majoral JP, Rodrigues J, Shi X, and Shen M
- Abstract
Curcumin (Cur), a traditional Chinese medicine extracted from natural plant rhizomes, has become a candidate drug for the treatment of diseases due to its anti-inflammatory, anticancer, antioxidant, and antibacterial activities. However, the poor water solubility and low bioavailability of Cur limit its therapeutic effects for clinical applications. A variety of nanocarriers have been successfully developed to improve the water solubility, in vivo distribution, and pharmacokinetics of Cur, as well as to enhance the ability of Cur to polarize macrophages and relieve macrophage oxidative stress or anti-apoptosis, thus accelerating the therapeutic effects of Cur on inflammatory diseases. Herein, we review the design and development of diverse Cur nanoformulations in recent years and introduce the biomedical applications and potential therapeutic mechanisms of Cur nanoformulations in common inflammatory diseases, such as arthritis, neurodegenerative diseases, respiratory diseases, and ulcerative colitis, by regulating macrophage behaviors. Finally, the perspectives of the design and preparation of future nanocarriers aimed at efficiently exerting the biological activity of Cur are briefly discussed.
- Published
- 2022
- Full Text
- View/download PDF
34. Functionalized Nitroimidazole Scaffold Construction and Their Pharmaceutical Applications: A 1950-2021 Comprehensive Overview.
- Author
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Gupta R, Sharma S, Singh R, Vishwakarma RA, Mignani S, and Singh PP
- Abstract
Nitroimidazole represents one of the most essential and unique scaffolds in drug discovery since its discovery in the 1950s. It was K. Maeda in Japan who reported in 1953 the first nitroimidazole as a natural product from Nocardia mesenterica with antibacterial activity, which was later identified as Azomycin 1 (2-nitroimidazole) and remained in focus until now. This natural antibiotic was the starting point for synthesizing numerous analogs and regio-isomers, leading to several life-saving drugs and clinical candidates against a number of diseases, including infections (bacterial, viral, parasitic) and cancers, as well as imaging agents in medicine/diagnosis. In the present decade, the nitroimidazole scaffold has again been given two life-saving drugs (Delamanid and Pretomanid) used to treat MDR (multi-drug resistant) tuberculosis. Keeping in view the highly successful track-record of the nitroimidazole scaffold in providing breakthrough therapeutic drugs, this comprehensive review focuses explicitly on presenting the activity profile and synthetic chemistry of functionalized nitroimidazole (2-, 4- and 5-nitroimidazoles as well as the fused nitroimidazoles) based drugs and leads published from 1950 to 2021. The present review also presents the miscellaneous examples in each class. In addition, the mutagenic profile of nitroimidazole-based drugs and leads and derivatives is also discussed.
- Published
- 2022
- Full Text
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35. Engineered Neutral Phosphorous Dendrimers Protect Mouse Cortical Neurons and Brain Organoids from Excitotoxic Death.
- Author
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Posadas I, Romero-Castillo L, Ronca RA, Karpus A, Mignani S, Majoral JP, Muñoz-Fernández M, and Ceña V
- Subjects
- Animals, Brain metabolism, Cells, Cultured, Glutamic Acid pharmacology, Mice, N-Methylaspartate, Neurons metabolism, Organoids metabolism, Rats, Receptors, Glutamate, Receptors, N-Methyl-D-Aspartate metabolism, Dendrimers pharmacology, Neuroprotective Agents pharmacology
- Abstract
Nanoparticles are playing an increasing role in biomedical applications. Excitotoxicity plays a significant role in the pathophysiology of neurodegenerative diseases, such as Alzheimer's or Parkinson's disease. Glutamate ionotropic receptors, mainly those activated by N-methyl-D-aspartate (NMDA), play a key role in excitotoxic death by increasing intraneuronal calcium levels; triggering mitochondrial potential collapse; increasing free radicals; activating caspases 3, 9, and 12; and inducing endoplasmic reticulum stress. Neutral phosphorous dendrimers, acting intracellularly, have neuroprotective actions by interfering with NMDA-mediated excitotoxic mechanisms in rat cortical neurons. In addition, phosphorous dendrimers can access neurons inside human brain organoids, complex tridimensional structures that replicate a significant number of properties of the human brain, to interfere with NMDA-induced mechanisms of neuronal death. Phosphorous dendrimers are one of the few nanoparticles able to gain access to the inside of neurons, both in primary cultures and in brain organoids, and to exert pharmacological actions by themselves.
- Published
- 2022
- Full Text
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36. Phosphorus dendron nanomicelles as a platform for combination anti-inflammatory and antioxidative therapy of acute lung injury.
- Author
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Li J, Chen L, Li C, Fan Y, Zhan M, Sun H, Mignani S, Majoral JP, Shen M, and Shi X
- Subjects
- Animals, Anti-Inflammatory Agents therapeutic use, Antioxidants pharmacology, Antioxidants therapeutic use, Cytokines metabolism, Disease Models, Animal, Lung pathology, Mice, NF-kappa B metabolism, Phosphorus, Reactive Oxygen Species metabolism, Acute Lung Injury drug therapy, Acute Lung Injury pathology, Curcumin, Dendrimers pharmacology
- Abstract
Rationale: Development of novel nanomedicines to inhibit pro-inflammatory cytokine expression and reactive oxygen species (ROS) generation for anti-inflammatory therapy of acute lung injury (ALI) remains challenging. Here, we present a new nanomedicine platform based on tyramine-bearing two dimethylphosphonate sodium salt (TBP)-modified amphiphilic phosphorus dendron (C11G3) nanomicelles encapsulated with antioxidant drug curcumin (Cur). Methods: C11G3-TBP dendrons were synthesized via divergent synthesis and self-assembled to generate nanomicelles in a water environment to load hydrophobic drug Cur. The created C11G3-TBP@Cur nanomicelles were well characterized and systematically examined in their cytotoxicity, cellular uptake, intracellular ROS elimination, pro-inflammatory cytokine inhibition and alveolar macrophages M2 type repolarization in vitro , and evaluated to assay their anti-inflammatory and antioxidative therapy effects of ALI mice model through pro-inflammatory cytokine expression level in bronchoalveolar lavage fluid and lung tissue, histological analysis and micro-CT imaging detection of lung tissue injury in vivo . Results: The nanomicelles with rigid phosphorous dendron structure enable high-capacity and stable Cur loading. Very strikingly, the drug-free C11G3-TBP micelles exhibit excellent cytocompatibility and intrinsic anti-inflammatory activity through inhibition of nuclear transcription factor- kappa B, thus causing repolarization of alveolar macrophages from M1 type to anti-inflammatory M2 type. Taken together with the strong ROS scavenging property of the encapsulated Cur, the developed nanomicelles enable effective therapy of inflammatory alveolar macrophages in vitro and an ALI mouse model in vivo after atomization administration. Conclusion: The created phosphorus dendron nanomicelles can be developed as a general nanomedicine platform for combination anti-inflammatory and antioxidative therapy of inflammatory diseases., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)
- Published
- 2022
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37. Crown Macromolecular Derivatives: Stepwise Design of New Types of Polyfunctionalized Phosphorus Dendrimers.
- Author
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Karpus A, Mignani S, Zablocka M, and Majoral JP
- Subjects
- Catalysis, Nanomedicine, Dendrimers chemistry, Phosphorus chemistry
- Abstract
Phosphorus dendrimers are used for many applications in different domains including nanomedicine as cargo of drugs or as species active per se but also in a variety of other fields ranging from nanoscience to catalysis. Their properties depend on the nature of their internal structure and mainly of the diversity and versatility of the functional groups located on their outer shell. Therefore, there is a need to diversify their structure in order to use them for new applications and to propose alternative synthetic pathways to be built easily, at each step and in high yield a family of original stable phosphorus dendrimers of different generations. Such a goal is illustrated in this report with the original synthesis of 14 new phosphorus dendrimers of generation 0 to 2 and the possibility to modify at will their internal structure and the nature of their functional end groups.
- Published
- 2022
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38. Engineered phosphorus dendrimers as powerful non-viral nanoplatforms for gene delivery: a great hope for the future of cancer therapeutics.
- Author
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Mignani S, Shi X, Bryszewska M, Shcharbin D, and Majoral JP
- Abstract
During the past two decades, tremendous progress has been made in the dendrimer-based delivery of therapeutic molecules including, for instance, small molecules, macromolecules, and genes. This review deals with recent successes in the development of promising biocompatible phosphorus dendrimers, a specific type of dendrimer, to deliver genes to treat cancers., Competing Interests: The authors declare that they have no conflicts of interest., (© The Author(s) 2022.)
- Published
- 2022
- Full Text
- View/download PDF
39. Blood Compatibility of Amphiphilic Phosphorous Dendrons-Prospective Drug Nanocarriers.
- Author
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Suty S, Oravczova V, Garaiova Z, Subjakova V, Ionov M, Shcharbin D, Simonikova Z, Bartek P, Zvarik M, Shi X, Mignani S, Majoral JP, Bryszewska M, Hianik T, and Waczulikova I
- Abstract
Dendrons are branched synthetic polymers suitable for preparation of nanosized drug delivery systems. Their interactions with biological systems are mainly predetermined by their chemical structure, terminal groups, surface charge, and the number of branched layers (generation). Any new compound intended to be used, alone or in combination, for medical purposes in humans must be compatible with blood. This study combined results from in vitro experiments on human blood and from laboratory experiments designed to assess the effect of amphiphilic phosphorous dendrons on blood components and model membranes, and to examine the presence and nature of interactions leading to a potential safety concern. The changes in hematological and coagulation parameters upon the addition of dendrons in the concentration range of 2-10 µM were monitored. We found that only the combination of higher concentration and higher generation of the dendron affected the selected clinically relevant parameters: it significantly decreased platelet count and plateletcrit, shortened thrombin time, and increased activated partial thromboplastin time. At the same time, occasional small-sized platelet clumps in blood films under the light microscope were observed. We further investigated aggregation propensity of the positively charged dendrons in model conditions using zwitterionic and negatively charged liposomes. The observed changes in size and zeta potential indicated the electrostatic nature of the interaction. Overall, we proved that the low-generation amphiphilic phosphorous dendrons were compatible with blood within the studied concentration range. However, interactions between high-generation dendrons at bulk concentrations above 10 µM and platelets and/or clotting factors cannot be excluded.
- Published
- 2021
- Full Text
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40. Functionalized Dendrimer Platforms as a New Forefront Arsenal Targeting SARS-CoV-2: An Opportunity.
- Author
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Mignani S, Shi X, Karpus A, Lentini G, and Majoral JP
- Abstract
The novel human coronavirus SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) has caused a pandemic. There are currently several marketed vaccines and many in clinical trials targeting SARS-CoV-2. Another strategy is to repurpose approved drugs to decrease the burden of the COVID-19 (official name for the coronavirus disease) pandemic. as the FDA (U.S. Food and Drug Administration) approved antiviral drugs and anti-inflammatory drugs to arrest the cytokine storm, inducing the production of pro-inflammatory cytokines. Another view to solve these unprecedented challenges is to analyze the diverse nanotechnological approaches which are able to improve the COVID-19 pandemic. In this original minireview, as promising candidates we analyze the opportunity to develop biocompatible dendrimers as drugs themselves or as nanocarriers against COVID-19 disease. From the standpoint of COVID-19, we suggest developing dendrimers as shields against COVID-19 infection based on their capacity to be incorporated in several environments outside the patients and as important means to stop transmission of SARS-CoV-2.
- Published
- 2021
- Full Text
- View/download PDF
41. First-in-Class Phosphorus Dendritic Framework, a Wide Surface Functional Group Palette Bringing Noteworthy Anti-Cancer and Anti-Tuberculosis Activities: What Lessons to Learn?
- Author
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Mignani S, Bignon J, Shi X, and Majoral JP
- Subjects
- Animals, Antineoplastic Agents therapeutic use, Antitubercular Agents therapeutic use, Dendrimers chemistry, Humans, Molecular Structure, Nanomedicine methods, Nanoparticles chemistry, Nanoparticles therapeutic use, Neoplasms drug therapy, Phosphorus chemistry, Tuberculosis drug therapy, Dendrimers pharmacology, Nanomedicine trends, Phosphorus pharmacology
- Abstract
Based on phenotypic screening, the major advantages of phosphorus dendrimers and dendrons as drugs allowed the discovery of new therapeutic applications, for instance, as anti-cancer and anti-tuberculosis agents. These biological activities depend on the nature of the chemical groups (neutral or cationic) on their surface as well as their generation. As lessons to learn, in the oncology domain, the increase in the generation of metallo-dendrimers is in the same direction as the anti-proliferative activities, in contrast to the development of polycationic dendrimers, where the most potent anti-tuberculosis phosphorus dendrimer was observed to have the lowest generation (G0). The examples presented in this original analysis of phosphorus dendrimers and dendrons provide support for the lessons learned and for the development of new nanoparticles in nanomedicine.
- Published
- 2021
- Full Text
- View/download PDF
42. Comparison of the effects of dendrimer, micelle and silver nanoparticles on phospholipase A2 structure.
- Author
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Terehova M, Dzmitruk V, Abashkin V, Kirakosyan G, Ghukasyan G, Bryszewska M, Pedziwiatr-Werbicka E, Ionov M, Gómez R, de la Mata FJ, Mignani S, Shi X, Majoral JP, Sukhodola A, and Shcharbin D
- Subjects
- Animals, Cattle, Micelles, Phospholipases A2, Silver, Dendrimers, Metal Nanoparticles, Nanoparticles
- Abstract
The interaction of nanoparticles (NP) with proteins (the so-called 'protein corona') is a huge challenge in attempting to apply them in personalized nanomedicine. We have analyzed the interaction between A) two 'soft' NPs (a cationic phosphorus dendrimer of generation 3; a cationic phosphorus amphiphilic dendron of generation 2), and B) one 'hard' nanoparticle (silver NP covered with cationic carbosilane dendritic moieties); and membrane-bound protein phospholipase A2 from bovine pancreas. The hard and soft NPs have differences in the nature of their interactions with phospholipase A2. This enzyme surrounds hard AgNP, whereas dendrimer and amphiphilic dendron form aggregates/micelles with phospholipase A2. There is a difference in action of phospholipase A2 bound to the core of dendrimer, and of micelles formed from non-covalent interactions between the amphiphilic dendron. These data are important in understanding the nature of interaction between different kinds of nanoparticles and proteins., (Copyright © 2021 Elsevier B.V. All rights reserved.)
- Published
- 2021
- Full Text
- View/download PDF
43. From Riluzole to Dexpramipexole via Substituted-Benzothiazole Derivatives for Amyotrophic Lateral Sclerosis Disease Treatment: Case Studies.
- Author
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Mignani S, Majoral JP, Desaphy JF, and Lentini G
- Subjects
- Animals, Benzothiazoles chemistry, Benzothiazoles pharmacology, Clinical Trials as Topic, Drug Approval, Drug Evaluation, Preclinical, Humans, Neuroprotective Agents pharmacology, Small Molecule Libraries chemical synthesis, Small Molecule Libraries pharmacology, Toluene analogs & derivatives, Toluene chemistry, Treatment Outcome, Amyotrophic Lateral Sclerosis drug therapy, Benzothiazoles chemical synthesis, Neuroprotective Agents chemical synthesis, Pramipexole chemistry, Riluzole chemistry
- Abstract
The 1,3-benzothiazole (BTZ) ring may offer a valid option for scaffold-hopping from indole derivatives. Several BTZs have clinically relevant roles, mainly as CNS medicines and diagnostic agents, with riluzole being one of the most famous examples. Riluzole is currently the only approved drug to treat amyotrophic lateral sclerosis (ALS) but its efficacy is marginal. Several clinical studies have demonstrated only limited improvements in survival, without benefits to motor function in patients with ALS. Despite significant clinical trial efforts to understand the genetic, epigenetic, and molecular pathways linked to ALS pathophysiology, therapeutic translation has remained disappointingly slow, probably due to the complexity and the heterogeneity of this disease. Many other drugs to tackle ALS have been tested for 20 years without any success. Dexpramipexole is a BTZ structural analog of riluzole and was a great hope for the treatment of ALS. In this review, as an interesting case study in the development of a new medicine to treat ALS, we present the strategy of the development of dexpramipexole, which was one of the most promising drugs against ALS.
- Published
- 2020
- Full Text
- View/download PDF
44. In Search of a Phosphorus Dendrimer-Based Carrier of Rose Bengal: Tyramine Linker Limits Fluorescent and Phototoxic Properties of a Photosensitizer.
- Author
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Sztandera K, Marcinkowska M, Gorzkiewicz M, Janaszewska A, Laurent R, Zabłocka M, Mignani S, Majoral JP, and Klajnert-Maculewicz B
- Subjects
- Animals, Carcinoma, Basal Cell pathology, Cell Death, Drug Carriers chemistry, Fluorescent Dyes chemistry, Mice, Photochemotherapy, Photosensitizing Agents chemistry, Reactive Oxygen Species metabolism, Singlet Oxygen, Skin Neoplasms pathology, Tumor Cells, Cultured, Carcinoma, Basal Cell drug therapy, Dendrimers chemistry, Phosphorus chemistry, Photosensitizing Agents pharmacology, Rose Bengal chemistry, Skin Neoplasms drug therapy, Tyramine chemistry
- Abstract
Photodynamic therapy (PDT) is a skin cancer treatment alternative to chemotherapy and radiotherapy. This method exploits three elements: a phototoxic compound (photosensitizer), light source and oxygen. Upon irradiation by light of a specific wavelength, the photosensitizer generates reactive oxygen species triggering the cascade of reactions leading to cell death. The positive therapeutic effect of PDT may be limited due to low solubility, low tumor specificity and inefficient cellular uptake of photosensitizers. A promising approach to overcome these obstacles involves the use of nanocarrier systems. The aim of this initial study was to determine the potential of the application of phosphorus dendrimers as carriers of a photosensitizer-rose bengal (RB). The primary goal involved the synthesis and in vitro studies of covalent drug-dendrimer conjugates. Our approach allowed us to obtain RB-dendrimer conjugates with the use of tyramine as an aromatic linker between the carrier and the drug. The compounds were characterized by FT-IR,
1 H NMR,13 C NMR,31 P NMR, size and zeta potential measurements and spectrofluorimetric analysis. The dialysis to check the drug release from the conjugate, flow cytometry to specify intracellular uptake, and singlet oxygen generation assay were also applied. Finally, we used MTT assay to determine the biological activity of the tested compounds. The results of our experiments indicate that the conjugation of RB to phosphorus dendrimers via the tyramine linker decreases photodynamic activity of RB.- Published
- 2020
- Full Text
- View/download PDF
45. Donecopride, a Swiss army knife with potential against Alzheimer's disease.
- Author
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Rochais C, Lecoutey C, Hamidouche K, Giannoni P, Gaven F, Cem E, Mignani S, Baranger K, Freret T, Bockaert J, Rivera S, Boulouard M, Dallemagne P, and Claeysen S
- Subjects
- Amyloid beta-Peptides metabolism, Amyloid beta-Protein Precursor metabolism, Aniline Compounds, Animals, Brain metabolism, Disease Models, Animal, Maze Learning, Mice, Mice, Transgenic, Piperidines, Rats, Alzheimer Disease drug therapy
- Abstract
Background and Purpose: We recently identified donecopride as a pleiotropic compound able to inhibit AChE and to activate 5-HT
4 receptors. Here, we have assessed the potential therapeutic effects of donecopride in treating Alzheimer's disease (AD)., Experimental Approach: We used two in vivo animal models of AD, transgenic 5XFAD mice and mice exposed to soluble amyloid-β peptides and, in vitro, primary cultures of rat hippocampal neurons. Pro-cognitive and anti-amnesic effects were evaluated with novel object recognition, Y-maze, and Morris water maze tests. Amyloid load in mouse brain was measured ex vivo and effects of soluble amyloid-β peptides on neuronal survival and neurite formation determined in vitro., Key Results: In vivo, chronic (3 months) administration of donecopride displayed potent anti-amnesic properties in the two mouse models of AD, preserving learning capacities, including working and long-term spatial memories. These behavioural effects were accompanied by decreased amyloid aggregation in the brain of 5XFAD mice and, in cultures of rat hippocampal neurons, reduced tau hyperphosphorylation. In vitro, donecopride increased survival in neuronal cultures exposed to soluble amyloid-β peptides, improved the neurite network and provided neurotrophic benefits, expressed as the formation of new synapses., Conclusions and Implications: Donecopride acts like a Swiss army knife, exhibiting a range of sustainable symptomatic therapeutic effects and potential disease-modifying effects in models of AD. Clinical trials with this promising drug candidate will soon be undertaken to confirm its therapeutic potential in humans., (© 2019 The British Pharmacological Society.)- Published
- 2020
- Full Text
- View/download PDF
46. Immunoreactivity changes of human serum albumin and alpha-1-microglobulin induced by their interaction with dendrimers.
- Author
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Serchenya T, Shcharbin D, Shyrochyna I, Sviridov O, Terekhova M, Dzmitruk V, Abashkin V, Apartsin E, Mignani S, Majoral JP, Ionov M, and Bryszewska M
- Subjects
- Antibodies, Monoclonal metabolism, Antigens metabolism, Dendrimers chemistry, Estradiol metabolism, Humans, Static Electricity, Thyroxine metabolism, Alpha-Globulins immunology, Dendrimers metabolism, Serum Albumin, Human immunology
- Abstract
Dendrimers are hyperbranched polymers for delivery of therapeutic genetic material to cancer cells. The fine tuning chemical modifications of dendrimers allow for the modification of the composition. The architecture and the properties of dendrimers are key factors to improve their in vitro and in vivo properties such as biocompatibility with cells and tissues and their pharmacokinetic/pharmacodynamic behavior. The side effects of dendrimers on structure and function of proteins is an important question that must be addressed. We herein describe the effect of newly synthesized piperidine-based cationic phosphorous dendrimers of 2 generations and commercial cationic, neutral and anionic poly(amidoamine) (PAMAM) dendrimers of 4th generation on immunochemical properties of 2 serum proteins: human serum albumin (HSA) and alpha-1-microglobulin (A1M). Both can bind and transfer ligands in blood, including hormones, fatty acids, toxins and drugs, and have immunoreactivity properties. Comparing the effects of piperidinium-terminated phosphorus and cationic, neutral and anionic PAMAM dendrimers on HSA and A1M, we conclude that, in the case of equimolar complexes, these dendrimers had no significant effect on immunoreactivity of proteins. In contrast, the formation of complexes in which a protein is fully bound to dendrimers leads to partial (1.2-2.3 times) reduction in protein immunoreactivity. The most important fact is that dendrimer-induced change in immunoreactivity of proteins is not complete, even if the protein is entirely bound by dendrimers. This means that the application of dendrimers in vivo will not totally hamper the immunoreactivity of these proteins and antibodies., (Copyright © 2019 Elsevier B.V. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
47. Targeted tumor dual mode CT/MR imaging using multifunctional polyethylenimine-entrapped gold nanoparticles loaded with gadolinium.
- Author
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Zhou B, Xiong Z, Wang P, Peng C, Shen M, Mignani S, Majoral JP, and Shi X
- Subjects
- Animals, Cell Line, Tumor, Colloids chemistry, Contrast Media chemistry, Female, Folic Acid chemistry, HeLa Cells, Hep G2 Cells, Humans, Magnetic Resonance Imaging methods, Mice, Mice, Inbred BALB C, Mice, Inbred C57BL, Mice, Nude, Particle Size, Polyethylene Glycols chemistry, Tomography, X-Ray Computed methods, Gadolinium chemistry, Gold chemistry, Metal Nanoparticles chemistry, Polyethyleneimine chemistry
- Abstract
We report the construction and characterization of polyethylenimine (PEI)-entrapped gold nanoparticles (AuNPs) chelated with gadolinium (Gd) ions for targeted dual mode tumor CT/MR imaging in vivo. In this work, polyethylene glycol (PEG) monomethyl ether-modified PEI was sequentially modified with Gd chelator and folic acid (FA)-linked PEG (FA-PEG) was used as a template to synthesize AuNPs, followed by Gd(III) chelation and acetylation of the remaining PEI surface amines. The formed FA-targeted PEI-entrapped AuNPs loaded with Gd (FA-Gd-Au PENPs) were well characterized in terms of structure, composition, morphology, and size distribution. We show that the FA-Gd-Au PENPs with an Au core size of 3.0 nm are water dispersible, colloidally stable, and noncytotoxic in a given concentration range. Thanks to the coexistence of Au and Gd elements within one nanoparticulate system, the FA-Gd-Au PENPs display a better X-ray attenuation property than clinical iodinated contrast agent (e.g. Omnipaque) and reasonable r
1 relaxivity (1.1 mM-1 s-1 ). These properties allow the FA-targeted particles to be used as an efficient nanoprobe for dual mode CT/MR imaging of tumors with excellent FA-mediated targeting specificity. With the demonstrated organ biocompatibility, the designed FA-Gd-Au PENPs may hold a great promise to be used as a nanoprobe for CT/MR dual mode imaging of different FA receptor-overexpressing tumors.- Published
- 2018
- Full Text
- View/download PDF
48. Doxorubicin-Conjugated PAMAM Dendrimers for pH-Responsive Drug Release and Folic Acid-Targeted Cancer Therapy.
- Author
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Zhang M, Zhu J, Zheng Y, Guo R, Wang S, Mignani S, Caminade AM, Majoral JP, and Shi X
- Abstract
We present here the development of multifunctional doxorubicin (DOX)-conjugated poly(amidoamine) (PAMAM) dendrimers as a unique platform for pH-responsive drug release and targeted chemotherapy of cancer cells. In this work, we covalently conjugated DOX onto the periphery of partially acetylated and folic acid (FA)-modified generation 5 (G5) PAMAM dendrimers through a pH-sensitive cis -aconityl linkage to form the G5.NHAc-FA-DOX conjugates. The formed dendrimer conjugates were well characterized using different methods. We show that DOX release from the G5.NHAc-FA-DOX conjugates follows an acid-triggered manner with a higher release rate under an acidic pH condition (pH = 5 or 6, close to the acidic pH of tumor microenvironment) than under a physiological pH condition. Both in vitro cytotoxicity evaluation and cell morphological observation demonstrate that the therapeutic activity of dendrimer-DOX conjugates against cancer cells is absolutely related to the DOX drug released. More importantly, the FA conjugation onto the dendrimers allowed a specific targeting to cancer cells overexpressing FA receptors (FAR), and allowed targeted inhibition of cancer cells. The developed G5.NHAc-FA-DOX conjugates may be used as a promising nanodevice for targeted cancer chemotherapy.
- Published
- 2018
- Full Text
- View/download PDF
49. Hydrogels of Polycationic Acetohydrazone-Modified Phosphorus Dendrimers for Biomedical Applications: Gelation Studies and Nucleic Acid Loading.
- Author
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Apartsin EK, Grigoryeva AE, Malrin-Fournol A, Ryabchikova EI, Venyaminova AG, Mignani S, Caminade AM, and Majoral JP
- Abstract
In this work, we report the assemblage of hydrogels from phosphorus dendrimers in the presence of biocompatible additives and the study of their interactions with nucleic acids. As precursors for hydrogels, phosphorus dendrimers of generations 1⁻3 based on the cyclotriphosphazene core and bearing ammonium or pyridinium acetohydrazones (Girard reagents) on the periphery have been synthesized. The gelation was done by the incubation of dendrimer solutions in water or phosphate-buffered saline in the presence of biocompatible additives (glucose, glycine or polyethylene glycol) to form physical gels. Physical properties of gels have been shown to depend on the gelation conditions. Transmission electron microscopy revealed structural units and well-developed network structures of the hydrogels. The hydrogels were shown to bind nucleic acids efficiently. In summary, hydrogels of phosphorus dendrimers represent a useful tool for biomedical applications.
- Published
- 2018
- Full Text
- View/download PDF
50. New Ways to Treat Tuberculosis Using Dendrimers as Nanocarriers.
- Author
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Mignani S, Tripathi RP, Chen L, Caminade AM, Shi X, and Majoral JP
- Abstract
Tuberculosis (TB) is a contagious infection that usually attacks not only the lungs, but also brain and spine. More than twenty drugs have been developed for the treatment of TB, but most of them were developed some years ago. They are used in different combinations. Isoniazid and Rifampicin are examples of the five first line TB drugs, whereas, for instance, Levofloxacin, Kanamycin and Linezolid belong to the second line drugs that are used for the treatment of drug resistant TB. Several new bicyclic nitroimidazoles (e.g., Delamanid) without mutagenic effects were developed. New TB drugs need to provide several main issues such as more effective, less toxic, and less expensive for drug resistant TB. Besides polymeric, metal-based nanoparticles, polymeric micelles and polymers, dendrimer nanostructures represent ideal delivery vehicles and offer high hopes for the future of nanomedicine. In this original review, we present and analyze the development of anti-TB drugs in combination with dendrimers. Few articles have highlighted the encapsulation of anti-TB drugs with dendrimers. Due to their unique structure, dendrimers represent attractive candidates for the encapsulation and conjugation of other anti-TB drugs presenting important drawbacks (e.g., solubility, toxicity, low bioavailability) that hinder their development, including clinic trials.
- Published
- 2018
- Full Text
- View/download PDF
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