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Padroni L, De Marco L, Fiano V, Milani L, Marmiroli G, Giraudo MT, Macciotta A, Ricceri F, Sacerdote C. Identifying MicroRNAs Suitable for Detection of Breast Cancer: A Systematic Review of Discovery Phases Studies on MicroRNA Expression Profiles. Int J Mol Sci 2023; 24:15114. [PMID: 37894794 PMCID: PMC10607026 DOI: 10.3390/ijms242015114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 10/09/2023] [Accepted: 10/10/2023] [Indexed: 10/29/2023] Open
Abstract
The analysis of circulating tumor cells and tumor-derived materials, such as circulating tumor DNA, circulating miRNAs (cfmiRNAs), and extracellular vehicles provides crucial information in cancer research. CfmiRNAs, a group of short noncoding regulatory RNAs, have gained attention as diagnostic and prognostic biomarkers. This review focuses on the discovery phases of cfmiRNA studies in breast cancer patients, aiming to identify altered cfmiRNA levels compared to healthy controls. A systematic literature search was conducted, resulting in 16 eligible publications. The studies included a total of 585 breast cancer cases and 496 healthy controls, with diverse sample types and different cfmiRNA assay panels. Several cfmiRNAs, including MIR16, MIR191, MIR484, MIR106a, and MIR193b, showed differential expressions between breast cancer cases and healthy controls. However, the studies had a high risk of bias and lacked standardized protocols. The findings highlight the need for robust study designs, standardized procedures, and larger sample sizes in discovery phase studies. Furthermore, the identified cfmiRNAs can serve as potential candidates for further validation studies in different populations. Improving the design and implementation of cfmiRNA research in liquid biopsies may enhance their clinical diagnostic utility in breast cancer patients.
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Affiliation(s)
- Lisa Padroni
- Unit of Cancer Epidemiology, Città Della Salute e Della Scienza University-Hospital and Center for Cancer Prevention (CPO), Via Santena 7, 10126 Turin, Italy; (L.P.); (L.D.M.); (G.M.)
| | - Laura De Marco
- Unit of Cancer Epidemiology, Città Della Salute e Della Scienza University-Hospital and Center for Cancer Prevention (CPO), Via Santena 7, 10126 Turin, Italy; (L.P.); (L.D.M.); (G.M.)
| | - Valentina Fiano
- Unit of Cancer Epidemiology, Department of Medical Sciences, University of Turin, 10126 Turin, Italy;
| | - Lorenzo Milani
- Centre for Biostatistics, Epidemiology and Public Health (C-BEPH), Department of Clinical and Biological Sciences, University of Turin, 10043 Orbassano, Italy; (L.M.); (M.T.G.); (A.M.); (F.R.)
| | - Giorgia Marmiroli
- Unit of Cancer Epidemiology, Città Della Salute e Della Scienza University-Hospital and Center for Cancer Prevention (CPO), Via Santena 7, 10126 Turin, Italy; (L.P.); (L.D.M.); (G.M.)
| | - Maria Teresa Giraudo
- Centre for Biostatistics, Epidemiology and Public Health (C-BEPH), Department of Clinical and Biological Sciences, University of Turin, 10043 Orbassano, Italy; (L.M.); (M.T.G.); (A.M.); (F.R.)
| | - Alessandra Macciotta
- Centre for Biostatistics, Epidemiology and Public Health (C-BEPH), Department of Clinical and Biological Sciences, University of Turin, 10043 Orbassano, Italy; (L.M.); (M.T.G.); (A.M.); (F.R.)
| | - Fulvio Ricceri
- Centre for Biostatistics, Epidemiology and Public Health (C-BEPH), Department of Clinical and Biological Sciences, University of Turin, 10043 Orbassano, Italy; (L.M.); (M.T.G.); (A.M.); (F.R.)
| | - Carlotta Sacerdote
- Unit of Cancer Epidemiology, Città Della Salute e Della Scienza University-Hospital and Center for Cancer Prevention (CPO), Via Santena 7, 10126 Turin, Italy; (L.P.); (L.D.M.); (G.M.)
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Macciotta A, Catalano A, Giraudo MT, Weiderpass E, Ferrari P, Freisling H, Colorado-Yohar SM, Santiuste C, Amiano P, Heath AK, Ward HA, Christakoudi S, Vineis P, Singh D, Vaccarella S, Schulze MB, Hiensch AE, Monninkhof EM, Katzke V, Kaaks R, Tumino R, Lazzarato F, Milani L, Agudo A, Dahm CC, Baglietto L, Perduca V, Severi G, Grioni S, Panico S, Ardanaz E, Borch KB, Benebo FO, Braaten T, Sánchez MJ, Giachino C, Sacerdote C, Ricceri F. Mediating Role of Lifestyle Behaviors in the Association between Education and Cancer: Results from the European Prospective Investigation into Cancer and Nutrition. Cancer Epidemiol Biomarkers Prev 2023; 32:132-140. [PMID: 36306379 DOI: 10.1158/1055-9965.epi-22-0777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 09/07/2022] [Accepted: 10/25/2022] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Many studies have shown that socioeconomic position (SEP) is associated with the incidence of malignant tumors at different sites. This study aims to estimate the association between educational level (as proxy for SEP) and cancer incidence and to understand whether the observed associations might be partially explained by lifestyle behaviors. METHODS The analyses were performed on data from the European Prospective Investigation into Cancer and Nutrition (EPIC) study, globally and by sex. We used Cox proportional hazards models together with mediation analysis to disentangle the total effect (TE) of educational level [measured through the Relative Index of Inequality (RII)] on cancer incidence into pure direct (PDE) and total indirect (TIE) effect, unexplained and explained by mediators, respectively. PDE and TIE were then combined to compute the proportions mediated (PM). RESULTS After an average of 14 years of follow-up, 52,422 malignant tumors were ascertained. Low educated participants showed higher risk of developing stomach, lung, kidney (in women), and bladder (in men) cancers, and, conversely, lower risk of melanoma and breast cancer (in post-menopausal women), when compared with more educated participants. Mediation analyses showed that portions of the TE of RII on cancer could be explained by site-specific related lifestyle behaviors for stomach, lung, and breast (in women). CONCLUSIONS Cancer incidence in Europe is determined at least in part by a socioeconomically stratified distribution of risk factors. IMPACT These observational findings support policies to reduce cancer occurrence by altering mediators, such as lifestyle behaviors, particularly focusing on underprivileged strata of the population.
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Affiliation(s)
- Alessandra Macciotta
- Department of Clinical and Biological Sciences, University of Turin, Turin, Italy
| | - Alberto Catalano
- Department of Clinical and Biological Sciences, University of Turin, Turin, Italy
| | | | | | - Pietro Ferrari
- International Agency for Cancer Research (IARC-WHO), Lyon, France
| | - Heinz Freisling
- International Agency for Cancer Research (IARC-WHO), Lyon, France
| | - Sandra M Colorado-Yohar
- Department of Epidemiology, Murcia Regional Health Council, IMIB-Arrixaca, Murcia, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
- Research Group on Demography and Health, National Faculty of Public Health, University of Antioquia, Medellín, Colombia
| | - Carmen Santiuste
- Department of Epidemiology, Murcia Regional Health Council, IMIB-Arrixaca, Murcia, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | - Pilar Amiano
- CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
- Ministry of Health of the Basque Government, Sub Directorate for Public Health and Addictions of Gipuzkoa, Biodonostia Health Research Institute, San Sebastian, Spain
| | - Alicia K Heath
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, United Kingdom
| | - Heather A Ward
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, United Kingdom
| | - Sofia Christakoudi
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, United Kingdom
- MRC Centre for Transplantation, King's College London, Great Maze Pond, London, United Kingdom
| | - Paolo Vineis
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, United Kingdom
| | - Deependra Singh
- International Agency for Cancer Research (IARC-WHO), Lyon, France
| | | | - Matthias B Schulze
- Department of Molecular Epidemiology, German Institute of Human Nutrition, Nuthetal, Germany
- Institute of Nutritional Science, University of Potsdam, Potsdam, Germany
| | - Anouk E Hiensch
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, the Netherlands
| | - Evelyn M Monninkhof
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, the Netherlands
| | - Verena Katzke
- Division of Cancer Epidemiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Rudolf Kaaks
- Division of Cancer Epidemiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Rosario Tumino
- Hyblean Association for Epidemiological Research, AIRE-ONLUS, Ragusa, Italy
| | - Fulvio Lazzarato
- Unit of Cancer Epidemiology, "Città della salute e della scienza" University-Hospital, Turin, Italy
| | - Lorenzo Milani
- Department of Medical Science, University of Turin, Turin, Italy
| | - Antonio Agudo
- Unit of Nutrition and Cancer, Catalan Institute of Oncology-ICO, L'Hospitalet de Llobregat, Barcelona, Spain
| | | | - Laura Baglietto
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
- Paris-Saclay University, UVSQ, Inserm, Gustave Roussy, "Exposome and Heredity" team, CESP, Villejuif, France
| | - Vittorio Perduca
- Paris-Saclay University, UVSQ, Inserm, Gustave Roussy, "Exposome and Heredity" team, CESP, Villejuif, France
- Laboratoire MAP5 (UMR CNRS 8145), Université de Paris, Paris, France
| | - Gianluca Severi
- Paris-Saclay University, UVSQ, Inserm, Gustave Roussy, "Exposome and Heredity" team, CESP, Villejuif, France
- Department of Statistics, Computer Science and Applications "G. Parenti" (DISIA), University of Florence, Florence, Italy
| | - Sara Grioni
- Epidemiology and Prevention Unit, Fondazione IRCCS Istituto Nazionale dei Tumori di Milano, Milano, Italy
| | - Salvatore Panico
- Dipartmento Di Medicina Clinica E Chirurgia Federico II University, Naples, Italy
| | - Eva Ardanaz
- CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
- Navarre Public Health Institute, Pamplona, Spain
| | - Kristin B Borch
- Department of Community Medicine, UiT, the Arctic University of Norway, Tromsø, Norway
| | - Faith O Benebo
- Department of Community Medicine, UiT, the Arctic University of Norway, Tromsø, Norway
| | - Tonje Braaten
- Department of Community Medicine, UiT, the Arctic University of Norway, Tromsø, Norway
| | - Maria-Jose Sánchez
- CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
- Escuela Andaluza de Salud Pública (EASP), Granada, Spain
- Instituto de Investigación Biosanitaria ibs, Granada, Spain
- Department of Preventive Medicine and Public Health, University of Granada, Granada, Spain
| | - Claudia Giachino
- Department of Clinical and Biological Sciences, University of Turin, Turin, Italy
| | - Carlotta Sacerdote
- Unit of Cancer Epidemiology, "Città della salute e della scienza" University-Hospital, Turin, Italy
| | - Fulvio Ricceri
- Department of Clinical and Biological Sciences, University of Turin, Turin, Italy
- Unit of Epidemiology, Regional Health Service ASL TO3, Grugliasco (TO), Italy
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Affiliation(s)
| | - Fulvio Ricceri
- Department of Clinical and Biological Sciences, University of Turin, Orbassano, Italy
- Unit of Epidemiology, Regional Health Service ASL TO3, Grugliasco, Italy
| | - Elena Rosso
- Department of Mathematics “Giuseppe Peano”, University of Turin, Turin, Italy
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Calandri E, Giraudo MT, Sirovich R, Ostan A, Pultrone M, Frantellizzi V, Conversano L, Bagnasacco P, Gallina S, De Vincentis G. Usefulness of 99mTc-pertechnetate SPECT-CT in thyroid tissue volumetry: phantom studies and a clinical case series. Curr Radiopharm 2022; 15:205-217. [PMID: 35021984 DOI: 10.2174/1874471015666220111145550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 10/18/2021] [Accepted: 10/25/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND An accurate measurement of the target volume is of primary importance in theragnostics of hyperthyroidism. OBJECTIVE Our purpose was to evaluate the accuracy of a threshold-based isocontour extraction procedure for thyroid tissue volumetry from SPECT-CT. METHODS Cylindrical vials with a fixed volume of 99mTcO4 at different activities were inserted into a neck phantom in two different thickness settings. Images were acquired by orienting the phantom in different positions, i.e., 40 planar images and 40 SPECT-CT. The fixed values of the iso-contouring threshold for SPECT and SPECT-CT were calculated by means of linear and spline regression models. Mean, Median, Standard Deviation, Standard Error, Mean Absolute Percentage Error and Root Mean-Square Error were computed. Any difference between the planar method, SPECT and SPECT-CT and the effective volume was evaluated by means of ANOVA and post-hoc tests. Moreover, planar and SPECT-CT acquisitions were performed in 8 patients with hyperthyroidism, considering relevant percentage differences greater than > 20 % from CT gold standard Results: Concerning phantom studies, the planar method shows higher values of each parameter than the other two methods. SPECT-CT shows lower variability. However, no significant differences were observed between SPECT and SPECT-CT measurements. In patients, relevant differences were found in 7 out of 9 lesions with the planar method, in 6 lesions with SPECT, but in only one with SPECT-CT Conclusion: Our study confirms the superiority of SPECT in volume measurement if compared with the planar method. A more accurate measurement can be obtained from SPECT-CT.
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Affiliation(s)
- Enrico Calandri
- Department of Medicine and Urgency, Nuclear Medicine Unit, Ospedale degli Infermi, Ponderano (BI), Italy
| | | | - Roberta Sirovich
- Department of Mathematics G. Peano, University of Torino, Torino, Italy
| | - Antonella Ostan
- Health Physics Department, Azienda Ospedaliera Maggiore della Carità, Novara, Italy
| | - Mirco Pultrone
- Department of Medicine and Urgency, Nuclear Medicine Unit, Ospedale degli Infermi, Ponderano (BI), Italy
| | - Viviana Frantellizzi
- Department of Radiological Sciences, Oncology and Anatomical Pathology, Nuclear Medicine Unit, “Sapienza” University, Rome, Italy
| | - Lucia Conversano
- Department of Medicine and Urgency, Nuclear Medicine Unit, Ospedale degli Infermi, Ponderano (BI), Italy
| | - Paolo Bagnasacco
- Department of Medicine and Urgency, Radiotherapy Unit, Ospedale degli Infermi, Ponderano (BI), Italy
| | - Sonya Gallina
- Department of Medicine and Urgency, Nuclear Medicine Unit, Ospedale degli Infermi, Ponderano (BI), Italy
| | - Giuseppe De Vincentis
- Department of Radiological Sciences, Oncology and Anatomical Pathology, Nuclear Medicine Unit, “Sapienza” University, Rome, Italy
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Giraudo MT, Falcone M, Cislaghi C. [The wave train of COVID-19 infections]. Epidemiol Prev 2021; 45:580-587. [PMID: 35001600 DOI: 10.19191/ep21.6.121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The present work studies the epidemic curve of COVID-19 in Italy between September 2020 and mid-June 2021 in terms of poussées, that is successive waves. There is obviously only one pandemic, although the virus has spread in the form of several variants, but the daily incidence trend can also be read in terms of overlapping of events that are different from each other or, in any case, induced by various phenomena. It can be hypothesized that in this way a succession of various waves was generated, which are modelled here using appropriate adaptation curves used in the study of epidemic data. Each curve corresponds approximately to the situation that would have occurred if no element had intervened to prevent the decrease of infections after the relative peak, while their overlap is considered to describe the subsequent increases. This interpolation has no predictive purpose, being purely descriptive over the time window under consideration. The discrepancies between the superposition of the modelling curves and the real epidemic curve are therefore also highlighted, especially in the transition periods between the various poussées. Finally, the analysis carried out allows to match the trend of the epidemic in the period considered with, on one hand, the series of events and, on the other, with the containment measures adopted which may have determined the succession of increases and decreases in the incidence of infections.
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Affiliation(s)
- Maria Teresa Giraudo
- Dipartimento di matematica "Giuseppe Peano", Università di Torino
- Gruppo AIE MADE
| | - Manuele Falcone
- Gruppo AIE MADE
- Azienda regionale di sanità della Toscana, Firenze
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Giraudo MT, Falcone M, Cadum E, Deandrea S, Scondotto S, Mattaliano A, Di Pietrantonj C, Bisceglia L, Duca P, Cislaghi C. [Rt or RDt, that is the question!]. Epidemiol Prev 2021; 44:42-50. [PMID: 33412793 DOI: 10.19191/ep20.5-6.s2.102] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The article compares two of the most followed indices in the monitoring of COVID-19 epidemic cases: the Rt and the RDt indices. The first was disseminated by the Italian National Institute of Health (ISS) and the second, which is more usable due to the lower difficulty of calculation and the availability of data, was adopted by various regional and local institutions.The rationale for the Rt index refers to that for the R0 index, the basic reproduction number, which is used by infectivologists as a measure of contagiousness of a given infectious agent in a completely susceptible population. The RDt index, on the other hand, is borrowed from the techniques of time series analysis for the trend of an event measurement that develops as a function of time. The RDt index does not take into account the time of infection, but the date of the diagnosis of positivity and for this reason it is defined as diagnostic replication index, as it aims to describe the intensity of the development of frequency for cases recognized as positive in the population.The comparison between different possible applications of the methods and the use of different types of monitoring data was limited to four areas for which complete individual data were available in March and April 2020. The main problems in the use of Rt, which is based on the date of symptoms onset, arise from the lack of completeness of this information due both to the difficulty in the recording and to the absence in asymptomatic subjects.The general trend of RDt, at least at an intermediate lag of 6 or 7 days, is very similar to that of Rt, as confirmed by the very high value of the correlation index between the two indices. The maximum correlation between Rt and RDt is reached at lag 7 with a value of R exceeding 0.97 (R2=0.944).The two indices, albeit formally distinct, are both valid; they show specific aspects of the phenomenon, but provide basically similar information to the public health decision-maker. Their distinction lies not so much in the method of calculation, rather in the use of different information, i.e., the beginning of symptoms and the swabs outcome.Therefore, it is not appropriate to make a judgment of preference for one of the two indices, but only to invite people to understand their different potentials so that they can choose the one they consider the most appropriate for the purpose they want to use it for.
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Affiliation(s)
| | | | | | - Silvia Deandrea
- Unità operativa complessa salute e ambiente e progetti innovativi
| | - Salvatore Scondotto
- Dipartimento per le attività sanitarie e osservatorio epidemiologico, Regione Siciliana, Palermo
| | | | - Carlo Di Pietrantonj
- Servizio di riferimento regionale di epidemiologia per la sorveglianza, la prevenzione e il controllo delle malattie infettive, Azienda sanitaria locale, Alessandria
| | - Lucia Bisceglia
- Area epidemiologia e care intelligence, Agenzia regionale strategica per la salute e il sociale Puglia, Bari
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Fasanelli F, Giraudo MT, Vineis P, Fiano V, Fiorito G, Grasso C, Polidoro S, Trevisan M, Grioni S, Krogh V, Mattiello A, Panico S, Giurdanella MC, Tumino R, De Marco L, Ricceri F, Sacerdote C. DNA methylation, colon cancer and Mediterranean diet: results from the EPIC-Italy cohort. Epigenetics 2019; 14:977-988. [PMID: 31179817 DOI: 10.1080/15592294.2019.1629230] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The biological mechanisms through which adherence to Mediterranean Diet (MD) protects against colon cancer (CC) are poorly understood. Evidence suggests that chronic inflammation may be implicated in the pathway. Both diet and CC are related to epigenetic regulation. We performed a nested case-control study on 161 pairs from the Italian component of the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, in which we looked for the methylation signals in DNA extracted from leucocytes associated with both CC and MD in 995 CpGs located in 48 inflammation genes. The DNA methylation signals detected in this analysis were validated in a subgroup of 47 case-control pairs and further replicated (where validated) in 95 new pairs by means of pyrosequencing. Among the CpG sites selected a-priori in inflammation-related genes, seven CpG sites were found to be associated with CC status and with MD, in line with its protective effect. Only two CpG sites (cg17968347-SERPINE1 and cg20674490-RUNX3) were validated using bisulphite pyrosequencing and, after replication, we found that DNA methylation of cg20674490-RUNX3 may be a potential molecular mediator explaining the protective effect of MD on CC onset. The use of a 'meet-in-the-middle' approach to identify the overlap between exposure and predictive markers of disease is innovative in studies on the relationship between diet and cancer, in which exposure assessment is difficult and the mechanisms through which the nutrients exert their protective effect is largely unknown.
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Affiliation(s)
- Francesca Fasanelli
- a Unit of Cancer Epidemiology- CeRMS, Department of Medical Sciences, University of Turin , Turin , Italy
| | | | - Paolo Vineis
- c Department of Epidemiology and Biostatistics, MRC-PHE Centre for Environment and Health, School of Public Health, Faculty of Medicine, Imperial College London , UK.,d Molecular and Genetic Epidemiology Unit, Italian Institute for Genomic Medicine (IIGM) , Turin , Italy
| | - Valentina Fiano
- a Unit of Cancer Epidemiology- CeRMS, Department of Medical Sciences, University of Turin , Turin , Italy
| | - Giovanni Fiorito
- d Molecular and Genetic Epidemiology Unit, Italian Institute for Genomic Medicine (IIGM) , Turin , Italy
| | - Chiara Grasso
- a Unit of Cancer Epidemiology- CeRMS, Department of Medical Sciences, University of Turin , Turin , Italy
| | - Silvia Polidoro
- d Molecular and Genetic Epidemiology Unit, Italian Institute for Genomic Medicine (IIGM) , Turin , Italy
| | - Morena Trevisan
- a Unit of Cancer Epidemiology- CeRMS, Department of Medical Sciences, University of Turin , Turin , Italy
| | - Sara Grioni
- e Epidemiology and Prevention Unit, Fondazione IRCCS Istituto Nazionale dei Tumori , Milan , Italy
| | - Vittorio Krogh
- e Epidemiology and Prevention Unit, Fondazione IRCCS Istituto Nazionale dei Tumori , Milan , Italy
| | - Amalia Mattiello
- f Department of Clinical Medicine and Surgery, Federico II University , Naples , Italy
| | - Salvatore Panico
- f Department of Clinical Medicine and Surgery, Federico II University , Naples , Italy
| | | | - Rosario Tumino
- g Cancer Registry, Department of Prevention, ASP , Ragusa , Italy
| | - Laura De Marco
- a Unit of Cancer Epidemiology- CeRMS, Department of Medical Sciences, University of Turin , Turin , Italy.,h Unit of Cancer Epidemiology, Città della Salute e della Scienza University-Hospital and Center for Cancer Prevention (CPO) , Turin , Italy
| | - Fulvio Ricceri
- i Epidemiology Unit, Regional Health Services ASL TO3 , Grugliasco , Italy.,j Department of Clinical and Biological Sciences, University of Turin , Turin , Italy
| | - Carlotta Sacerdote
- h Unit of Cancer Epidemiology, Città della Salute e della Scienza University-Hospital and Center for Cancer Prevention (CPO) , Turin , Italy
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Fasanelli F, Giraudo MT, Ricceri F, Valeri L, Zugna D. Marginal Time-Dependent Causal Effects in Mediation Analysis With Survival Data. Am J Epidemiol 2019; 188:967-974. [PMID: 30689682 DOI: 10.1093/aje/kwz016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 01/16/2019] [Accepted: 01/16/2019] [Indexed: 12/28/2022] Open
Abstract
The main aim of mediation analysis is to study the direct and indirect effects of an exposure on an outcome. To date, the literature on mediation analysis with multiple mediators has mainly focused on continuous and dichotomous outcomes. However, the development of methods for multiple mediation analysis of survival outcomes is still limited. Here we extend to survival outcomes a method for multiple mediation analysis based on the computation of appropriate weights. The approach considered has the advantages of not requiring specific models for mediators, allowing nonindependent mediators of any nature, and not relying on the assumption of rare outcomes. Simulation studies show good performance of the proposed estimator in terms of bias and coverage probability. The method is further applied to an example from a published study on prostate cancer mortality aimed at understanding the extent to which the effect of DNA methyltransferase 3b (DNMT3b) genotype on mortality was explained by DNA methylation and tumor aggressiveness. This approach can be used to quantify the marginal time-dependent direct and indirect effects carried by multiple indirect pathways, and software code is provided to facilitate its application.
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Affiliation(s)
- Francesca Fasanelli
- Cancer Epidemiology Unit, Department of Medical Sciences, School of Medicine, University of Turin, Turin, Italy
| | - Maria Teresa Giraudo
- Department of Mathematics "Giuseppe Peano," School of Sciences of Nature, University of Turin, Turin, Italy
| | - Fulvio Ricceri
- Department of Clinical and Biological Sciences, School of Medicine, University of Turin, Turin, Italy
- Unit of Epidemiology, Regional Health Service, Azienda Sanitaria Locale Torino 3, Turin, Italy
| | - Linda Valeri
- Department of Biostatistics, T.H. Chan School of Public Health, Harvard University, Boston, Massachusetts
| | - Daniela Zugna
- Cancer Epidemiology Unit, Department of Medical Sciences, School of Medicine, University of Turin, Turin, Italy
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Parodi E, Ferrero A, Perrone B, Saracco P, Giraudo MT, Regoli D. Current practice of iron prophylaxis in preterm and low birth weight neonates: A survey among Italian Neonatal Units. Pediatr Neonatol 2018; 59:581-585. [PMID: 29398552 DOI: 10.1016/j.pedneo.2018.01.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 09/21/2017] [Accepted: 01/12/2018] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Preterm babies are at high risk of iron deficiency. METHODS We investigated current practices regarding iron prophylaxis in preterm and low birth weight newborns among Local Neonatal Units (LNUs, n = 74) and Neonatal Intensive Care Units (NICUs, n = 20) of three Italian Regions (Piemonte, Marche and Lazio). RESULTS Birth weight is considered an indicative parameter in only 64% of LNUs and 71% of NICUs, with a significant difference between LNUs in the three regions (86%, 20% and 62%, respectively; p < 0.001). Iron is recommended to infants with a birth weight between 2000 and 2500 g in only 25% of LNUs and 21% of NICUs, and to late-preterm (gestational age between 34 and 37 weeks) in a minority of Units (26% of LNUs, 7% of NICUs). CONCLUSIONS Our pilot survey documents a great variability and the urgent need to standardize practices according to literature recommendations.
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Affiliation(s)
- Emilia Parodi
- Neonatology Unit, Ordine Mauriziano Hospital, Torino, Italy; Department of Pediatric and Public Health Sciences, University of Torino, Torino, Italy.
| | - Anna Ferrero
- Department of Pediatric and Public Health Sciences, University of Torino, Torino, Italy.
| | - Barbara Perrone
- Division of Neonatology and Neonatal Intensive Care Unit, Salesi Children's Hospital, Azienda Ospedaliera, Universitaria Ospedali Riuniti di Ancona, Ancona, Italy.
| | - Paola Saracco
- Department of Pediatric and Public Health Sciences, University of Torino, Torino, Italy; Pediatric Hematology Unit, "Città della Salute e della Scienza Hospital", Torino, Italy.
| | | | - Daniela Regoli
- Neonatal Intensive Care Unit, Department of Pediatrics and Child Neuropsychiatry, "Sapienza" University of Roma, Roma, Italy.
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10
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Agnoli C, Sieri S, Ricceri F, Giraudo MT, Masala G, Assedi M, Panico S, Mattiello A, Tumino R, Giurdanella MC, Krogh V. Adherence to a Mediterranean diet and long-term changes in weight and waist circumference in the EPIC-Italy cohort. Nutr Diabetes 2018; 8:22. [PMID: 29695712 PMCID: PMC5916888 DOI: 10.1038/s41387-018-0023-3] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 11/14/2017] [Accepted: 01/06/2018] [Indexed: 12/20/2022] Open
Abstract
Excessive calorie intake and physical inactivity are considered key determinants of the rapid worldwide increase in obesity prevalence, however the relationship between diet and weight gain is complex. We investigated associations between adherence to a Mediterranean diet and long-term changes in weight and waist circumference in volunteers recruited to the Italian section of the prospective European Prospective Investigation into Cancer and Nutrition (EPIC). We investigated 32,119 cohort members who provided anthropometric measures at recruitment and updated information on recall a mean of 12 years later. Adherence to a Mediterranean diet was assessed using the Italian Mediterranean Index (score range 0-11). Associations between index score and weight and waist changes were assessed by multivariate linear regression models. Risks of developing overweight/obesity and abdominal obesity were investigated by multivariate logistic models. Increasing Italian Mediterranean Index score (indicating better adherence) was associated with lower 5-year weight change in volunteers of normal weight at baseline (β -0.12, 95% CI -0.16 to -0.08 for 1 tertile increase in score), but not in those overweight/obese at baseline (P interaction between Index score and BMI 0.0001). High adherence was also associated with reduced risk of becoming overweight/obese (OR 0.91, 95% CI 0.84-0.99 third vs. first tertile); smaller 5-year change in waist circumference (β -0.09, 95% CI -0.14 to -0.03 for 1 tertile increase in score); and lower risk of abdominal obesity (OR 0.91, 95% CI 0.84-0.99 third vs. first tertile). Adherence to a traditional Italian Mediterranean diet may help prevent weight gain and abdominal obesity.
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Affiliation(s)
- Claudia Agnoli
- Epidemiology and Prevention Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Sabina Sieri
- Epidemiology and Prevention Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy.
| | - Fulvio Ricceri
- Unit of Epidemiology, Regional Health Service, Grugliasco, Turin, Italy
| | | | - Giovanna Masala
- Cancer Risk Factors and Lifestyle Epidemiology Unit, Cancer Research and Prevention Institute (ISPO), Florence, Italy
| | - Melania Assedi
- Cancer Risk Factors and Lifestyle Epidemiology Unit, Cancer Research and Prevention Institute (ISPO), Florence, Italy
| | - Salvatore Panico
- Department of Clinical and Experimental Medicine, Federico II University of Naples, Naples, Italy
| | - Amalia Mattiello
- Department of Clinical and Experimental Medicine, Federico II University of Naples, Naples, Italy
| | - Rosario Tumino
- Cancer Registry, Provincial Health Unit (ASP) Ragusa, Ragusa, Italy
| | | | - Vittorio Krogh
- Epidemiology and Prevention Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
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11
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Vinciguerra T, Brunati A, David E, Longo F, Pinon M, Ricceri F, Castellino L, Piga A, Giraudo MT, Tandoi F, Cisarò F, Dell Olio D, Isolato G, Romagnoli R, Salizzoni M, Calvo PL. Transient elastography for non-invasive evaluation of post-transplant liver graft fibrosis in children. Pediatr Transplant 2018; 22. [PMID: 29369488 DOI: 10.1111/petr.13125] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/15/2017] [Indexed: 12/15/2022]
Abstract
As graft survival in pediatric LT is often affected by progressive fibrosis, numerous centers carry out protocol liver biopsies. Follow-up biopsy protocols differ from center to center, but all biopsies are progressively spaced out, as time from transplant increases. Therefore, there is a need for non-invasive techniques to evaluate graft fibrosis progression in those children who have no clinical or serological signs of liver damage. Indirect markers, such as the APRI, should be relied on with caution because their sensitivity in predicting fibrosis can be strongly influenced by the etiology of liver disease, severity of fibrosis, and patient age. A valid alternative could be TE, a non-invasive technique already validated in adults, which estimates the stiffness of the cylindrical volume of liver tissue, 100-fold the size of a standard needle biopsy sample. The aims of this study were to evaluate the reliability of TE in children after LT and to compare both the TE and the APRI index results with the histological scores of fibrosis on liver biopsies. A total of 36 pediatric LT recipients were studied. All patients underwent both TE and biopsy within a year (median interval -0.012 months) at an interval from LT of 0.36 to 19.47 years (median 3.02 years). Fibrosis was assessed on the biopsy specimens at histology and staged according to METAVIR. There was a statistically significant correlation between TE stiffness values and METAVIR scores (P = .005). The diagnostic accuracy of TE for the diagnosis of significant fibrosis (F ≥ 2) was measured as the area under the curve (AUROC = 0.865), and it demonstrated that the method had a good diagnostic performance. APRI was not so accurate in assessing graft fibrosis when compared to METAVIR (AUROC = 0.592). A liver stiffness cutoff value of 5.6 kPa at TE was identified as the best predictor for a significant graft fibrosis (METAVIR F ≥ 2) on liver biopsy, with a 75% sensitivity, a 95.8% specificity, a 90% positive predictive value, and an 88.5% negative predictive value. These data suggest that TE may represent a non-invasive, reliable tool for the assessment of graft fibrosis in the follow-up of LT children, alerting the clinicians to the indication for a liver biopsy, with the aim of reducing the number of protocol liver biopsies.
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Affiliation(s)
- Tiziana Vinciguerra
- Gastroenterologia e Epatologia Pediatrica, Department of Pediatrics, Azienda Ospedaliera-Universitaria Citta`della Salute e della Scienza, Turin, Italy
| | - Andrea Brunati
- Liver Transplantation Center, Azienda Ospedaliera-Universitaria Città della Salute e della Scienza, University of Turin, Turin, Italy
| | - Ezio David
- Department of Pathology, Azienda Ospedaliera-Universitaria Citta`della Salute e della Scienza, Turin, Italy
| | - Filomena Longo
- Department of Clinical and Biological Sciences, University of Turin, Turin, Italy
| | - Michele Pinon
- Gastroenterologia e Epatologia Pediatrica, Department of Pediatrics, Azienda Ospedaliera-Universitaria Citta`della Salute e della Scienza, Turin, Italy
| | - Fulvio Ricceri
- Epidemiology Unit, Regional Health Services ASL TO3, Grugliasco, Italy.,Cancer Epidemiology Unit, Department of Medical Sciences, University of Turin, Turin, Italy
| | - Luisa Castellino
- Department of Mathematics "G. Peano", University of Turin, Turin, Italy
| | - Antonio Piga
- Department of Clinical and Biological Sciences, University of Turin, Turin, Italy
| | | | - Francesco Tandoi
- Liver Transplantation Center, Azienda Ospedaliera-Universitaria Città della Salute e della Scienza, University of Turin, Turin, Italy
| | - Fabio Cisarò
- Gastroenterologia e Epatologia Pediatrica, Department of Pediatrics, Azienda Ospedaliera-Universitaria Citta`della Salute e della Scienza, Turin, Italy
| | - Dominic Dell Olio
- Regional Transplant Center, Azienda Ospedaliera-Universitaria Città della Salute e della Scienza, Turin, Italy
| | - Giuseppe Isolato
- Institute of Diagnostic and Interventional Radiology, Azienda Ospedaliera-Universitaria Citta`della Salute e della Scienza, Turin, Italy
| | - Renato Romagnoli
- Liver Transplantation Center, Azienda Ospedaliera-Universitaria Città della Salute e della Scienza, University of Turin, Turin, Italy
| | - Mauro Salizzoni
- Liver Transplantation Center, Azienda Ospedaliera-Universitaria Città della Salute e della Scienza, University of Turin, Turin, Italy
| | - Pier Luigi Calvo
- Gastroenterologia e Epatologia Pediatrica, Department of Pediatrics, Azienda Ospedaliera-Universitaria Citta`della Salute e della Scienza, Turin, Italy
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12
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Priola AM, Priola SM, Gned D, Giraudo MT, Veltri A. Nonsuppressing normal thymus on chemical-shift MR imaging and anterior mediastinal lymphoma: differentiation with diffusion-weighted MR imaging by using the apparent diffusion coefficient. Eur Radiol 2017; 28:1427-1437. [PMID: 29143106 DOI: 10.1007/s00330-017-5142-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 09/14/2017] [Accepted: 10/18/2017] [Indexed: 12/22/2022]
Abstract
OBJECTIVES To prospectively evaluate usefulness of the apparent diffusion coefficient (ADC) in differentiating anterior mediastinal lymphoma from nonsuppressing normal thymus on chemical-shift MR, and to look at the relationship between patient age and ADC. METHODS Seventy-three young subjects (25 men, 48 women; age range, 9-29 years), who underwent chemical-shift MR and diffusion-weighted MR were divided into a normal thymus group (group A, 40 subjects), and a lymphoma group (group B, 33 patients). For group A, all subjects had normal thymus with no suppression on opposed-phase chemical-shift MR. Two readers measured the signal intensity index (SII) and ADC. Differences in SII and ADC between groups were tested using t-test. ADC was correlated with age using Pearson correlation coefficient. RESULTS Mean SII±standard deviation was 2.7±1.8% for group A and 2.2±2.4% for group B, with no significant difference between groups (P=.270). Mean ADC was 2.48±0.38x10-3mm2/s for group A and 1.24±0.23x10-3mm2/s for group B. A significant difference between groups was found (P<.001), with no overlap in range. Lastly, significant correlation was found between age and ADC (r=0.935, P<.001) in group A. CONCLUSIONS ADC of diffusion-weighted MR is a noninvasive and accurate parameter for differentiating lymphoma from nonsuppressing thymus on chemical-shift MR in young subjects. KEY POINTS • SII cannot differentiate mediastinal lymphoma from nonsuppressing normal thymus at visual assessment • ADC is useful for distinguishing nonsuppressing normal thymus from mediastinal lymphoma • ADC is more accurate than transverse-diameter and surface-area in this discrimination • ADC of normal thymus is age dependent and increases with increasing age.
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Affiliation(s)
- Adriano Massimiliano Priola
- Department of Diagnostic Imaging, San Luigi Gonzaga University Hospital, Regione Gonzole 10, 10043, Orbassano, Torino, Italy.
| | - Sandro Massimo Priola
- Department of Diagnostic Imaging, San Luigi Gonzaga University Hospital, Regione Gonzole 10, 10043, Orbassano, Torino, Italy
| | - Dario Gned
- Department of Diagnostic Imaging, San Luigi Gonzaga University Hospital, Regione Gonzole 10, 10043, Orbassano, Torino, Italy
| | - Maria Teresa Giraudo
- Department of Mathematics, "Giuseppe Peano", University of Torino, Via Carlo Alberto 10, 10123, Torino, Italy
| | - Andrea Veltri
- Department of Diagnostic Imaging, San Luigi Gonzaga University Hospital, Regione Gonzole 10, 10043, Orbassano, Torino, Italy
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13
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Ricceri F, Giraudo MT, Fasanelli F, Milanese D, Sciannameo V, Fiorini L, Sacerdote C. Diet and endometrial cancer: a focus on the role of fruit and vegetable intake, Mediterranean diet and dietary inflammatory index in the endometrial cancer risk. BMC Cancer 2017; 17:757. [PMID: 29132343 PMCID: PMC5683600 DOI: 10.1186/s12885-017-3754-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 11/03/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Endometrial cancer is the fourth most common cancer in European women. The major risk factors for endometrial cancer are related to the exposure of endometrium to estrogens not opposed to progestogens, that can lead to a chronic endometrial inflammation. Diet may play a role in cancer risk by modulating chronic inflammation. METHODS In the framework of a case-control study, we recruited 297 women with newly diagnosed endometrial cancer and 307 controls from Northern Italy. Using logistic regression, we investigated the role of fruit and vegetable intake, adherence to the Mediterranean diet (MD), and the dietary inflammatory index (DII) in endometrial cancer risk. RESULTS Women in the highest quintile of vegetable intake had a statistically significantly lower endometrial cancer risk (adjusted OR 5th quintile vs 1st quintile: 0.34, 95% CI 0.17-0.68). Women with high adherence to the MD had a risk of endometrial cancer that was about half that of women with low adherence to the MD (adjusted OR: 0.51, 95% CI 0.39-0.86). A protective effect was detected for all the lower quintiles of DII, with the highest protective effect seen for the lowest quintile (adjusted OR 5th quintile vs 1st quintile: 3.28, 95% CI 1.30-8.26). CONCLUSIONS These results suggest that high vegetable intake, adherence to the MD, and a low DII are related to a lower endometrial cancer risk, with several putative connected biological mechanisms that strengthen the biological plausibility of this association.
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Affiliation(s)
- Fulvio Ricceri
- Department of Clinical and Biological Sciences, University of Turin, Regione Gonzole, 10, Orbassano(TO), Italy.,Unit of Epidemiology, Regional Health Service ASL TO3, Via Sabaudia, 164, Grugliasco(TO), Italy
| | - Maria Teresa Giraudo
- Department of Mathematics "Giuseppe Peano", University of Turin, Via Carlo Alberto, 10, Turin, Italy
| | - Francesca Fasanelli
- Unit of Cancer Epidemiology, Città della Salute e della Scienza University-Hospital and University of Turin, Via Santena 7, Turin, Italy
| | - Dario Milanese
- Department of Mathematics "Giuseppe Peano", University of Turin, Via Carlo Alberto, 10, Turin, Italy
| | - Veronica Sciannameo
- Unit of Epidemiology, Regional Health Service ASL TO3, Via Sabaudia, 164, Grugliasco(TO), Italy
| | - Laura Fiorini
- Unit of Cancer Epidemiology, Città della Salute e della Scienza University-Hospital and University of Turin, Via Santena 7, Turin, Italy
| | - Carlotta Sacerdote
- Unit of Cancer Epidemiology, Città della Salute e della Scienza University-Hospital and University of Turin, Via Santena 7, Turin, Italy.
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14
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Fasanelli F, Zugna D, Giraudo MT, Krogh V, Grioni S, Panico S, Mattiello A, Masala G, Caini S, Tumino R, Frasca G, Sciannameo V, Ricceri F, Sacerdote C. Abdominal adiposity is not a mediator of the protective effect of Mediterranean diet on colorectal cancer. Int J Cancer 2017; 140:2265-2271. [DOI: 10.1002/ijc.30653] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 01/12/2017] [Accepted: 01/31/2017] [Indexed: 11/09/2022]
Affiliation(s)
- Francesca Fasanelli
- Unit of Cancer Epidemiology, Department of Medical Sciences; University of Turin and Città della Salute e della Scienza University-Hospital Center for Cancer Prevention (CPO); Turin Italy
| | - Daniela Zugna
- Unit of Cancer Epidemiology, Department of Medical Sciences; University of Turin and Città della Salute e della Scienza University-Hospital Center for Cancer Prevention (CPO); Turin Italy
| | | | - Vittorio Krogh
- Epidemiology and Prevention Unit; Fondazione IRCCS Istituto Nazionale dei Tumori; Milan Italy
| | - Sara Grioni
- Epidemiology and Prevention Unit; Fondazione IRCCS Istituto Nazionale dei Tumori; Milan Italy
| | - Salvatore Panico
- Department of Clinical Medicine and Surgery; Federico II University; Naples Italy
| | - Amalia Mattiello
- Department of Clinical Medicine and Surgery; Federico II University; Naples Italy
| | - Giovanna Masala
- Cancer Risk Factors and Lifestyle Epidemiology Unit Cancer Research and Prevention Institute - ISPO; Florence Italy
| | - Saverio Caini
- Cancer Risk Factors and Lifestyle Epidemiology Unit Cancer Research and Prevention Institute - ISPO; Florence Italy
| | - Rosario Tumino
- Cancer Registry, Department of Prevention; ASP; Ragusa Italy
| | | | - Veronica Sciannameo
- Unit of Epidemiology, Regional Health Service, Grugliasco; Turin Italy
- Department of Clinical and Biological Sciences; University of Turin; Orbassano (Torino) Italy
| | - Fulvio Ricceri
- Unit of Cancer Epidemiology, Department of Medical Sciences; University of Turin and Città della Salute e della Scienza University-Hospital Center for Cancer Prevention (CPO); Turin Italy
- Unit of Epidemiology, Regional Health Service, Grugliasco; Turin Italy
| | - Carlotta Sacerdote
- Unit of Cancer Epidemiology, Department of Medical Sciences; University of Turin and Città della Salute e della Scienza University-Hospital Center for Cancer Prevention (CPO); Turin Italy
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15
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Priola AM, Priola SM, Gned D, Giraudo MT, Brundu M, Righi L, Veltri A. Diffusion-weighted quantitative MRI of pleural abnormalities: Intra- and interobserver variability in the apparent diffusion coefficient measurements. J Magn Reson Imaging 2017; 46:769-782. [PMID: 28117923 DOI: 10.1002/jmri.25633] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 12/28/2016] [Indexed: 12/14/2022] Open
Abstract
PURPOSE To assess intra- and interobserver variability in the apparent diffusion coefficient (ADC) measurements of pleural abnormalities. MATERIALS AND METHODS Diffusion-weighted magnetic resonance imaging was performed in 34 patients to characterize pleural abnormalities, with a 1.5T unit at b values of 0/150/500/800 sec/mm2 . In two sessions held 3 months apart, on perfusion-free ADC maps, two independent readers measured the ADC of pleural abnormalities (two readings for each reader in each case) using different methods of region-of-interest (ROI) positioning. In three methods, freehand ROIs were drawn within tumor boundaries to encompass the entire lesion on one or more axial slices (whole tumor volume [WTV], three slices observer-defined [TSOD], single-slice [SS]), while in two methods one or more ROIs were placed on the more restricted areas (multiple small round ROI [MSR], one small round ROI [OSR]). Measurement variability between readings by each reader (intraobserver repeatability) and between readers in first reading (interobserver repeatability) were assessed using intraclass correlation coefficient (ICC) and coefficient of variation (CoV). Analysis of variance (ANOVA) was performed to compare ADC values between the different methods. The measurement time of each case for all methods in first reading was recorded and compared between methods and readers. RESULTS All methods demonstrated good (MSR, OSR) and excellent (WTV, TSOD, SS) intra- and interreader agreement, with best and worst repeatability in WTV (lower ICC, 0.977; higher CoV, 3.5%) and OSR (lower ICC, 0.625; higher CoV, 22.8%), respectively. The lower 95% confidence interval of ICC resulted in fair to moderate agreement for OSR (up to 0.379) and in excellent agreement for WTV, TSV, and SS (up to 0.918). ADC values of OSR and MSR were significantly lower compared to other methods (P < 0.001). The OSR and SS required less measurement time (10 and 21/22 sec, respectively) compared to the others (P < 0.0001), while the WTV required the longest measurement time (132/134 sec) (P < 0.0001). CONCLUSION ADC measurements of pleural abnormalities are repeatable. The SS method has excellent repeatability, similar to WTV, but requires significantly less measurement time. Thus, its use should be preferred in clinical practice. LEVEL OF EVIDENCE 4 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;46:769-782.
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Affiliation(s)
| | - Sandro Massimo Priola
- Department of Diagnostic Imaging, San Luigi Gonzaga University Hospital, Orbassano (Torino), Italy
| | - Dario Gned
- Department of Diagnostic Imaging, San Luigi Gonzaga University Hospital, Orbassano (Torino), Italy
| | | | - Maria Brundu
- Department of Diagnostic Imaging, San Luigi Gonzaga University Hospital, Orbassano (Torino), Italy
| | - Luisella Righi
- Department of Pathology, San Luigi Gonzaga University Hospital, Orbassano (Torino), Italy
| | - Andrea Veltri
- Department of Diagnostic Imaging, San Luigi Gonzaga University Hospital, Orbassano (Torino), Italy
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16
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Miglio G, Sabatino AD, Veglia E, Giraudo MT, Beccuti M, Cordero F. A computational analysis of S-(2-succino)cysteine sites in proteins. Biochim Biophys Acta 2015; 1864:211-8. [PMID: 26589354 DOI: 10.1016/j.bbapap.2015.11.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2015] [Revised: 10/19/2015] [Accepted: 11/13/2015] [Indexed: 12/31/2022]
Abstract
The adduction of fumaric acid to the sulfhydryl group of certain cysteine (Cys) residues in proteins via a Michael-like reaction leads to the formation of S-(2-succino)cysteine (2SC) sites. Although its role remains to be fully understood, this post-translational Cys modification (protein succination) has been implicated in the pathogenesis of diabetes/obesity and fumarate hydratase-related diseases. In this study, theoretical approaches to address sequence- and 3D-structure-based features possibly underlying the specificity of protein succination have been applied to perform the first analysis of the available data on the succinate proteome. A total of 182 succinated proteins, 205 modifiable, and 1750 non-modifiable sites have been examined. The rate of 2SC sites per protein ranged from 1 to 3, and the overall relative abundance of modifiable sites was 10.8%. Modifiable and non-modifiable sites were not distinguishable when the hydrophobicity of the Cys-flaking peptides, the acid dissociation constant value of the sulfhydryl groups, and the secondary structure of the Cys-containing segments were compared. By contrast, significant differences were determined when the accessibility of the sulphur atoms and the amino acid composition of the Cys-flaking peptides were analysed. Based on these findings, a sequence-based score function has been evaluated as a descriptor for Cys residues. In conclusion, our results indicate that modifiable and non-modifiable sites form heterogeneous subsets when features often discussed to describe Cys reactivity are examined. However, they also suggest that some differences exist, which may constitute the baseline for further investigations aimed at the development of predictive methods for 2SC sites in proteins.
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Affiliation(s)
- Gianluca Miglio
- Dipartimento di Scienza e Tecnologia del Farmaco, Università degli Studi di Torino, Turin, Italy.
| | | | - Eleonora Veglia
- Dipartimento di Scienza e Tecnologia del Farmaco, Università degli Studi di Torino, Turin, Italy
| | - Maria Teresa Giraudo
- Dipartimento di Matematica "Giuseppe Peano", Università degli Studi di Torino, Turin, Italy
| | - Marco Beccuti
- Dipartimento di Informatica, Università degli Studi di Torino, Turin, Italy
| | - Francesca Cordero
- Dipartimento di Informatica, Università degli Studi di Torino, Turin, Italy
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Ricceri F, Giraudo MT, Sieri S, Pala V, Masala G, Ermini I, Giurdanella MC, Martorana C, Mattiello A, Chiodini P, Vineis P, Sacerdote C. [Dietary habits and social differences: the experience of EPIC-Italy]. Epidemiol Prev 2015; 39:315-321. [PMID: 26554681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
OBJECTIVES to investigate the impact of socioeconomic status on dietary habits in Italy. DESIGN large Italian multicentric prospective cohort study. SETTING AND PARTICIPANTS more than 45,000 subjects recruited between 1993 and 1998 in five Italian centres (Turin, Varese, Florence, Naples, and Ragusa). Dietary habits, educational level, and other characteristics were collected at baseline using standardised questionnaires. MAIN OUTCOME MEASURES dietary habits collected for the EPIC study, grouped by food type and summarised by a Mediterranean dietary index. RESULTS we observed differences in dietary habits and in lifestyle habits by tertile of educational level. Principally, we noticed a positive association between higher education and healthy dietary habits (reduction in intake of processed meat, bread and rice, sweet drinks; increase in intake of fruit and vegetables, yoghurt, fish, olive oil, and tea). CONCLUSION a relationship between educational level and dietary habits is confirmed also in Italy, even if differences due to gender and residence area are present. This study shows an important role of dietary habits in health inequalities of the population with lower socioeconomic status.
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Affiliation(s)
- Fulvio Ricceri
- Servizio sovrazonale di epidemiologia, ASL TO 3, Grugliasco (TO).
- Unità di epidemiologia dei tumori, AOU Città della salute e della scienza, Università di Torino e Centro per la prevenzione oncologica (CPO), Torino
| | | | - Sabina Sieri
- Dipartimento di medicina preventiva e predittiva, Unità di epidemiologia e prevenzione, Fondazione IRCSS - Istituto nazionale dei tumori, Milano
| | - Valeria Pala
- Dipartimento di medicina preventiva e predittiva, Unità di epidemiologia e prevenzione, Fondazione IRCSS - Istituto nazionale dei tumori, Milano
| | - Giovanna Masala
- Struttura complessa di epidemiologia molecolare e nutrizionale, Istituto per lo studio e la prevenzione oncologica (ISPO), Firenze
| | - Ilaria Ermini
- Struttura complessa di epidemiologia molecolare e nutrizionale, Istituto per lo studio e la prevenzione oncologica (ISPO), Firenze
| | | | - Caterina Martorana
- Registro dei tumori, Dipartimento di prevenzione medica, Azienda sanitaria provinciale (ASP) Ragusa
| | - Amalia Mattiello
- Dipartimento di medicina clinica e chirurgia, Università Federico II, Napoli
| | - Paolo Chiodini
- Dipartimento di salute mentale e fisica e medicina preventiva, Seconda Università di Napoli
| | - Paolo Vineis
- Fondazione di genetica umana (HuGeF), Torino
- School of Public Health, Imperial College, Londra
| | - Carlotta Sacerdote
- Unità di epidemiologia dei tumori, AOU Città della salute e della scienza, Università di Torino e Centro per la prevenzione oncologica (CPO), Torino
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Ricceri F, Fasanelli F, Giraudo MT, Sieri S, Tumino R, Mattiello A, Vagliano L, Masala G, Quirós JR, Travier N, Sánchez MJ, Larranaga N, Chirlaque MD, Ardanaz E, Tjonneland A, Olsen A, Overvad K, Chang-Claude J, Kaaks R, Boeing H, Clavel-Chapelon F, Kvaskoff M, Dossus L, Trichopoulou A, Benetou V, Adarakis G, Bueno-de-Mesquita HBA, Peeters PH, Sund M, Andersson A, Borgquist S, Butt S, Weiderpass E, Skeie G, Khaw KT, Travis RC, Rinaldi S, Romieu I, Gunter M, Kadi M, Riboli E, Vineis P, Sacerdote C. Risk of second primary malignancies in women with breast cancer: Results from the European prospective investigation into cancer and nutrition (EPIC). Int J Cancer 2015; 137:940-8. [PMID: 25650288 DOI: 10.1002/ijc.29462] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 01/12/2015] [Indexed: 12/12/2022]
Abstract
Women with a diagnosis of breast cancer are at increased risk of second primary cancers, and the identification of risk factors for the latter may have clinical implications. We have followed-up for 11 years 10,045 women with invasive breast cancer from a European cohort, and identified 492 second primary cancers, including 140 contralateral breast cancers. Expected and observed cases and Standardized Incidence Ratios (SIR) were estimated using Aalen-Johansen Markovian methods. Information on various risk factors was obtained from detailed questionnaires and anthropometric measurements. Cox proportional hazards regression models were used to estimate the role of risk factors. Women with breast cancer had a 30% excess risk for second malignancies (95% confidence interval-CI 18-42) after excluding contralateral breast cancers. Risk was particularly elevated for colorectal cancer (SIR, 1.71, 95% CI 1.43-2.00), lymphoma (SIR 1.80, 95% CI 1.31-2.40), melanoma (2.12; 1.63-2.70), endometrium (2.18; 1.75-2.70) and kidney cancers (2.40; 1.57-3.52). Risk of second malignancies was positively associated with age at first cancer, body mass index and smoking status, while it was inversely associated with education, post-menopausal status and a history of full-term pregnancy. We describe in a large cohort of women with breast cancer a 30% excess of second primaries. Among risk factors for breast cancer, a history of full-term pregnancy was inversely associated with the risk of second primary cancer.
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Affiliation(s)
- Fulvio Ricceri
- Unit of Cancer Epidemiology-CERMS, Department of Medical Sciences, University of Turin and Città Della Salute E Della Scienza Hospital, Turin, Italy
- Department of Mathematics "G. Peano", University of Turin, Turin, Italy
| | - Francesca Fasanelli
- Unit of Cancer Epidemiology-CERMS, Department of Medical Sciences, University of Turin and Città Della Salute E Della Scienza Hospital, Turin, Italy
| | | | - Sabina Sieri
- Epidemiology and Prevention Unit, Fondazione IRCCS Istituto Nazionale Dei Tumori, Milano, Italy
| | - Rosario Tumino
- Cancer Registry and Histopathology Unit, ", Civile M.P. Arezzo" Hospital, ASP, Ragusa, Italy
| | - Amalia Mattiello
- Dipartimento Di Medicina Clinica E Chirurgia, Università Federico II, Napoli, Italy
| | - Liliana Vagliano
- Department of Public and Pediatric Health Sciences, University of Turin, Turin, Italy
| | - Giovanna Masala
- Molecular and Nutritional Epidemiology Unit, Cancer Research and Prevention Institute ISPO, Florence, Italy
| | | | - Noemie Travier
- Unit of Nutrition, Environment and Cancer, Cancer Epidemiology Research Programme, Institut Catalá d'Oncologia, Barcelona, Spain
| | - María-José Sánchez
- Andalusian School of Public Health, Granada Bio-Health Research Institute (Granada.IBS), Granada, Spain
- CIBER Epidemiología Y Salud Pública (CIBERESP), Spain
| | - Nerea Larranaga
- Public Division of Gipuzkoa, Basque Regional Health Department and CIBERESP, San Sebastian, Spain
| | - María-Dolores Chirlaque
- CIBER Epidemiología Y Salud Pública (CIBERESP), Spain
- Department of Epidemiology, Murcia Regional Health Authority, Murcia, Spain
| | - Eva Ardanaz
- CIBER Epidemiología Y Salud Pública (CIBERESP), Spain
- Navarra Public Health Institute, Pamplona, Spain
| | | | - Anja Olsen
- Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Kim Overvad
- Section for Epidemiology, Department of Public Health, Aarhus University, Aarhus, Denmark
| | - Jenny Chang-Claude
- Unit of Genetic Epidemiology, Division of Cancer Epidemiology, Deutsches Krebsforschungszentrum, Heidelberg, Germany
| | - Rudolf Kaaks
- Unit of Genetic Epidemiology, Division of Cancer Epidemiology, Deutsches Krebsforschungszentrum, Heidelberg, Germany
| | - Heiner Boeing
- Department of Epidemiology, German Institute of Human Nutrition Potsdam-Rehbrücke, Nuthetal, Germany
| | - Françoise Clavel-Chapelon
- Inserm, Centre for Research in Epidemiology and Population Health (CESP), U1018, Nutrition, Hormones and Women's Health Team, F, -94805, Villejuif, France
- University Paris Sud, UMRS 1018, F, -94805, Villejuif, France
- Institute Gustave Roussy, F, -94805, Villejuif, France
| | - Marina Kvaskoff
- Inserm, Centre for Research in Epidemiology and Population Health (CESP), U1018, Nutrition, Hormones and Women's Health Team, F, -94805, Villejuif, France
- University Paris Sud, UMRS 1018, F, -94805, Villejuif, France
- Institute Gustave Roussy, F, -94805, Villejuif, France
| | - Laure Dossus
- Inserm, Centre for Research in Epidemiology and Population Health (CESP), U1018, Nutrition, Hormones and Women's Health Team, F, -94805, Villejuif, France
- University Paris Sud, UMRS 1018, F, -94805, Villejuif, France
- Institute Gustave Roussy, F, -94805, Villejuif, France
| | - Antonia Trichopoulou
- WHO Collaborating Center for Food and Nutrition Policies, Department of Hygiene, Epidemiology and Medical Statistics, University of Athens Medical School, Athens, Greece
- Hellenic Health Foundation, Athens, Greece
| | - Vassiliki Benetou
- WHO Collaborating Center for Food and Nutrition Policies, Department of Hygiene, Epidemiology and Medical Statistics, University of Athens Medical School, Athens, Greece
| | | | - H B As Bueno-de-Mesquita
- National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
- Department of Gastroenterology and Hepatology, University Medical Centre, Utrecht, The Netherlands
- Department of Epidemiology and Biostatistics, the School of Public Health, Imperial College London, London, United Kingdom
- Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Petra H Peeters
- Department of Epidemiology, Julius Center for Health Sciences and Primary Care, University Medical Center, Utrecht, The Netherlands
| | - Malin Sund
- Department of Surgical and Perioperative Sciences/Surgery, Umea University, Umea, Sweden
| | - Anne Andersson
- Department of Radiation Sciences/Oncology, Umea University, Umea, Sweden
| | - Signe Borgquist
- Department of Oncology, Clinical Sciences, Lund University, Lund, Sweden
| | - Salma Butt
- Department of Surgery, Institute of Clinical Sciences, Skane University Hospital, Malmö, Sweden
| | - Elisabete Weiderpass
- Department of Community Medicine, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway
- Department of Research, Cancer Registry of Norway, Oslo, Norway
- Department of Medical Epidemiology and Biostatistics, Karolinska Institute, Stockholm, Sweden
- Department of Genetic Epidemiology, Folkhälsan Research Center, Helsinki, Finland
| | - Guri Skeie
- Department of Community Medicine, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway
| | - Kay-Tee Khaw
- Clinical Gerontology Unit, University of Cambridge School of Clinical Medicine, Addenbrooke's Hospital, Cambridge, United Kingdom
| | - Ruth C Travis
- Cancer Epidemiology Unit, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Sabina Rinaldi
- International Agency for Research on Cancer (IARC), Lyon, France
| | - Isabelle Romieu
- International Agency for Research on Cancer (IARC), Lyon, France
| | - Marc Gunter
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, United Kingdom
| | - Mai Kadi
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, United Kingdom
| | - Elio Riboli
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, United Kingdom
| | - Paolo Vineis
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, United Kingdom
- Unit of molecular and genetic epidemiology, Human Genetics Foundation (HuGeF), Turin, Italy
| | - Carlotta Sacerdote
- Unit of Cancer Epidemiology-CERMS, Department of Medical Sciences, University of Turin and Città Della Salute E Della Scienza Hospital, Turin, Italy
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Priola AM, Priola SM, Volpicelli G, Giraudo MT, Martino V, Fava C, Veltri A. Accuracy of 64-row multidetector CT in the diagnosis of surgically treated acute abdomen. Clin Imaging 2013; 37:902-7. [PMID: 23764231 DOI: 10.1016/j.clinimag.2013.02.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2013] [Accepted: 02/22/2013] [Indexed: 10/26/2022]
Abstract
OBJECTIVE To assess the accuracy of 64-row computed tomography (CT) in the differential diagnosis of acute abdomen in the emergency department. MATERIALS AND METHODS Prospective analysis of 181 patients with surgically treated acute abdomen. RESULTS In 158/181 cases, CT was totally concordant with surgical repertoire. Partial concordance was found in 15 cases. Overall sensitivity was 87.3% when only cases of complete concordance were considered, 95.6% if also partial concordance cases were included. CONCLUSION CT showed high reliability in the differential diagnosis of acute abdomen surgically treated, although associated conditions can sometimes be missed.
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Affiliation(s)
- Adriano Massimiliano Priola
- Department of Diagnostic and Interventional Radiology, University of Turin, San Luigi Gonzaga University Hospital, Regione Gonzole 10, 10043, Orbassano (Torino), Italy.
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Giraudo MT, Greenwood PE, Sacerdote L. How Sample Paths of Leaky Integrate-and-Fire Models Are Influenced by the Presence of a Firing Threshold. Neural Comput 2011; 23:1743-67. [DOI: 10.1162/neco_a_00143] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Neural membrane potential data are necessarily conditional on observation being prior to a firing time. In a stochastic leaky integrate-and-fire model, this corresponds to conditioning the process on not crossing a boundary. In the literature, simulation and estimation have almost always been done using unconditioned processes. In this letter, we determine the stochastic differential equations of a diffusion process conditioned to stay below a level S up to a fixed time t1 and of a diffusion process conditioned to cross the boundary for the first time at t1. This allows simulation of sample paths and identification of the corresponding mean process. Differences between the mean of free and conditioned processes are illustrated, as well as the role of noise in increasing these differences.
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Affiliation(s)
| | - Priscilla E. Greenwood
- Department of Mathematical Sciences, University of Copenhagen, DK-2100, Copenhagen, Denmark
| | - Laura Sacerdote
- Department of Mathematics G. Peano, University of Turin, 10123 Turin, Italy, and Neurosciences Institute of Turin, 10126 Turin, Italy
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Abstract
To relate the noise intensity with a periodically modulated input signal in a single neuron stochastic model we introduce a diffusion model with both time modulated drift and diffusion coefficient. Such a model is the continuous version of a Stein model with time oscillating frequencies for the Poisson processes describing the inputs impinging on the neuron. We focus here on some aspects of the resonance phenomenon for such a model. We compare the corresponding interspike interval distribution with the analogous distribution for a model sharing the same parameter values, but with constant noise intensity. Examples with two different levels for this noise intensity are discussed. The enhancement of the height of the peaks in the interspike interval distribution appearing at the modulation period, the improvement of the phase locking behavior and an enlargement of the noise ranges where a resonance like behavior arises are the main features observed in the considered cases.
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Affiliation(s)
- Maria Teresa Giraudo
- Department of Mathematics, University of Torino, V.C. Alberto 10, 10123 Torino, Italy.
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Abstract
The effects of taking into account in a perfect integrate and fire model of neuronal activity the spatial localization of the synapses are studied by superposing to the diffusion a simple discrete jump component. Different criteria are employed to assess the role of excitatory and inhibitory discrete contributions. Comparisons are performed with respect to the case where contributions coming from synapses more distal from the trigger zone are summed up in a continuous model. A systematic study of the output frequency and of the inter spike interval coefficient of variation (CV) is performed by means of examples as the model parameters are varied.
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Affiliation(s)
- Maria Teresa Giraudo
- Department of Mathematics, University of Torino, V.C. Alberto 10, 10123 Turin, Italy.
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Abstract
The interspike distribution can be modelled as the first-passage-time distribution of suitable diffusion processes with biologically meaningful boundaries. Since various mathematical difficulties arise when one attempts to obtain closed form solutions for first-passage-time problems, one can resort to simulation methods in order to study the problem. In this paper we pinpoint possible overestimations connected with simulations of first-passage-times for diffusion processes and propose a suitable simulation technique to determine the moments and the distribution of the firing times. After checking the validity of the proposed method in some instances where numerical evaluations for such quantities are available, we apply the simulation algorithm to model the spiking activity by means of a particular diffusion process constrained by a suitable time varying threshold.
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Affiliation(s)
- M T Giraudo
- Department of Mathematics, University of Torino, Italy
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Abstract
Aiming at an improvement of the existing neuronal models, we consider a mixed process ensuing from the superposition of continuous diffusions and of Poisson time-distributed sequence of impulses and focus our attention on the moments of the firing time. In particular, we consider three different instances: the large jumps model in which each jump causes the neuron firing, the reset model characterized by jumps towards the resting potential and a more general model where constant amplitude excitatory and inhibitory jumps are superimposed on diffusion. By resorting to analytical arguments and to numerical computations, the main behavioral differences of the considered models are outlined.
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Affiliation(s)
- M T Giraudo
- Department of Mathematics, University of Torino, Italy. giraudo,
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Nizzari M, Sesti F, Giraudo MT, Virginio C, Cattaneo A, Torre V. Single-channel properties of cloned cGMP-activated channels from retinal rods. Proc Biol Sci 1993; 254:69-74. [PMID: 7505453 DOI: 10.1098/rspb.1993.0128] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Single-channel properties of a cloned channel activated by cyclic GMP have been analysed. The mRNA encoding for the channel was injected into oocytes of Xenopus laevis and the current flowing through a single ionic channel activated by cGMP was studied in excised patches under voltage-clamp conditions. The ionic channel activated by cGMP had a single-channel conductance of 32 +/- 2 pS at +120 mV and 25 +/- 4 pS at -120 mV, and its conductance was not significantly affected by increasing the cGMP concentration from 20 microM to 200 microM. The single-channel currents in the presence of NH+4, Na+, K+, Li+ and Rb+ in the medium bathing the cytoplasmic side of the membrane at +140 mV were 5.3, 4.7, 3.8, 1.3 and 0.8 pA, respectively. The single-channel current in the presence of Cs+ was less than 0.5 pA. Ca2+ and Mg2+ (both 0.5 mM) in the presence of 100 microM cGMP did not appreciably affect the channel activity at membrane potentials more negative than -80 mV, whereas at +100 mV they reduced the single-channel conductance by about threefold. The ionic selectivity and the blockage by divalent cations of the native channel found in amphibian rods and in the cloned channel from bovine rods are quite similar. However, the cloned channel has well-resolved openings, especially at positive membrane voltages, whereas the native channel is characterized by a continuous flickering between the open and closed state.
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Affiliation(s)
- M Nizzari
- Dipartimento di Fisica, Università di Genova, Italy
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