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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Expressão de genes de repressão gênica em tumor primário em relação à presença ou ausência de células metastáticas ocultas na medula óssea em pacientes com câncer de mama / Expression of genes involved in transcriptional repression in the primary tumor of breast cancer patients in the presence or absence of occult metastatic cells in the bone marrow

Abreu, Ana Paula Santana de 25 August 2006 (has links)
Estudos sugerem que a presença de células metastáticas ocultas em medula óssea pode ser fator prognóstico em câncer de mama. Além disso, é possível que um perfil gênico tumoral específico, caracterizado por repressão da expressão gênica, esteja associado à detecção de células tumorais na medula óssea. O silenciamento de genes é controlado pela desacetilação de histonas e metilação de DNA, esta última catalisada por enzimas DNA metil transferases. Outro alvo de metil-transferases são as histonas, e histona H3 quando sofre metilação em lisina 9, gera sítio de ligação a proteínas HP1 (Heterocromatin protein-1 ou cromobox). Membros da família HP1 (HP1Hsalfa, HP1Hsbeta e HP1HsY) participam da formação da heterocromatina e da regulação da expressão de genes. Logo, nosso objetivo foi determinar no tumor primário de mama, a expressão de HP1Hsalfa, HP1Hsbeta e HP1Hsy , que participam da repressão gênica, em relação à presença ou ausência de células metastáticas ocultas na medula óssea. Neste estudo foram incluídas 37 pacientes de forma prospectiva, atendidas no Instituto Brasileiro de Controle do Câncer (IBCC) no período de junho de 2004 a julho de 2005, com diagnóstico histopatológico de carcinoma invasivo de mama, estádio clínico (EC) I (16,2%), II (51,4%) ou III (32,4%), segundo a classificação patológica. A idade mediana das pacientes foi 63 anos (41 a 90) e 62.2% delas encontravam-se na pós-menopausa, sendo que 24.3% relatava história familiar para câncer de mama. O tipo histológico predominante foi carcinoma ductal invasivo (89.2% dos casos), sendo, o restante, representado por carcinoma lobular invasivo (10.8%). Foram coletadas amostras de tumor primário de mama e de aspirado de medula óssea de cada paciente. A presença de células metastáticas ocultas (CMO) na medula óssea (MO) foi detectada através da expressão de citoqueratina 19 (CK19) pelo método de nested RT-PCR. A expressão relativa dos genes HP1Hsalfa, HP1Hsbeta e HP1Hsy foi determinada no tumor primário, usando-se a técnica de RT-PCR em tempo real. Presença de CMO foi detectada na MO de 20 pacientes (54.1%). Não observamos diferença na expressão de HP1Hs? (1,93 ± 2,25 MO- vs 3,84 ± 5,53 MO+), HP1Hs? (6,74 ± 6,31 MO- vs 6,49 ± 5,86 MO+) e HP1Hs? (24,58 ± 11,14 MO- vs 24,91 ± 15,88 MO+) entre as amostras tumorais de pacientes com presença (MO+) ou ausência (MO-) de micrometástase medular. Também não observamos variação da expressão de genes HP1 em relação ao comprometimento linfonodal, dimensão e grau histológico do tumor, expressão tumoral de receptores de estrógeno e estado menopausal da paciente. A expressão de HP1Hsalfa em tumores de pacientes com câncer de mama ERBB2 negativos, entretanto, foi maior do que em tumores ERBB2 positivos. Nossos dados indicam que em tumores de mama, a expressão de HP1Hsalfa, HP1Hsbeta e HP1Hsy não parece se associar à presença de células ocultas em medula óssea / Studies suggest that the presence of occult metastatic cells (OMC) in the bone marrow (BM) may be a prognostic factor in breast cancer. Besides, it is possible that a specific tumor gene profile, characterized by repression of gene expression, may be associated to the presence of tumoral cells in the bone marrow. Gene silencing is controlled by histone deacetylation and DNA methylation, the last one catalized by enzymes DNA methyltransferases (DNMTs). Histones are another target of methyltransferases, and methylation of histone H3 on lysine-9 generate a binding site for HP1 proteins (Heterocromatin protein-1 or chromobox). Members of the HP1 family (HP1Hsalfa, HP1Hsbeta e HP1Hsy) take part in heterochromatin formation and gene expression regulation. Hence, our aim was to determine in the primary tumor of the breast, the expression of HP1Hsalfa, HP1Hsbeta e HP1Hsy, which participate in gene repression, in the presence or absence of occult metastatic cells in the bone marrow. In this study, 37 patients treated at Instituto Brasileiro de Controle do Câncer, from June 2004 to July 2005, with invasive breast cancer histopathologically confirmed, pathological clinical stages I (16,2%), II (51,4%) or III (32,4), were included. The median age of the patients was 63 years (41 to 90), 62.2% were post-menopausal and 24.3% reported family history of breast cancer. Invasive ductal carcinoma was diagnosed in most patients (89.2%), and invasive lobular carcinoma was detected in the other patients (10.8%). Tumor samples and bone marrow aspirates were obtained from each patient. The presence of CMO in BM was detected by keratin-19 (CK19) expression by nested RT-PCR. The relative expression of the genes HP1Hsalfa, HP1Hsbeta e HP1Hsy was determined by real-time RT-PCR. Occult metastatic cells (OMC) in BM were detected in 20 patients (54.1%). No differences were observed in the expression of HP1Hs? (1,93 ± 2,25 BM- vs 3,84 ± 5,53 BM+), HP1Hsalfa (6,74 ± 6,31 BM- vs 6,49 ± 5,86 BM+) and HP1Hsbeta (24,58 ± 11,14 BM- vs 24,91 ± 15,88 BM+) between tumor samples of BM+ patients and BM- patients. Variations of HP1 gene expression were neither observed according to lymph node involvement, tumor size, histological grade, estrogen receptor status and menopausal status. However, HP1Hsbeta expression in ERBB2-negative tumors was higher than in ERBB2-positive tumors. Our data indicate that in breast cancer tumors, expression of HP1Hsalfa, HP1Hsbeta e HP1Hsy does not seem to be associated with the presence of occult metastatic cells in the bone marrow
132

Estudo do perfilamento gênico tumoral e de marcadores de doença residual mínima (CK19 e c-ErbB-2) através de RT-PCR quantitativo na fração mononuclear do sangue periférico em pacientes com câncer de mama durante o tratamento / Study of tumor gene profiling and minimal residual disease markers (CK19 and c-ErbB-2) by quantitative RT-PCR in peripheral blood mononuclear fraction in patients with breast cancer during chemotherapy

Kuniyoshi, Renata Kelly 13 November 2013 (has links)
INTRODUÇÃO: De acordo com a estimativa de 2012 do INCA, eram esperados 52.680 novos casos de câncer de mama no Brasil, com um risco estimado de 52 casos a cada 100 mil mulheres. Estes dados mostram a necessidade da identificação de biomarcadores efetivos para rastreamento precoce e seguimento destas mulheres durante seu tratamento. Neste trabalho, para a avaliação de potenciais biomarcadores desta doença, foi idealizado um modelo laboratorial específico que avalie tanto a capacidade de um dado biomarcador rastrear um tumor inicial de mama, bem como testar o seu potencial valor para o seguimento de mulheres já diagnosticadas durante seu tratamento. Este modelo baseia-se na avaliação de células tumorais circulantes e perfilamento gênico tumoral. MÉTODOS: Amostras biológicas (sangue periférico e tumor) de 167 pacientes diagnosticadas com carcinoma mamário estadios I, II e III com indicação de quimioterapia adjuvante para: a) avaliação da presença de células tumorais circulantes através da expressão de CK19 e HER2 na Fração Mononuclear do Sangue Periférico (FMNSP) por RT-PCR quantitativo e b) perfilamento gênico tumoral através da análise da expressão de 21 genes relacionados a importantes processos de carcinogênese mamária em amostras de tecido parafinado por ensaio multiplex de RT-PCR quantitativo utilizando o sistema Plexor®. RESULTADOS: Foi observada uma correlação significativa entre CK19 e HER2 na primeira coleta e queda da concentração de HER2 no SP durante o tratamento; porém, não foi percebida queda significativa do CK19 ao longo do estudo. A expressão de HER2 na segunda coleta de pacientes positivas para HER2 na primeira coleta tendeu a se correlacionar significativamente com um pior Intervalo Livre de Doença (ILD). Através da padronização da pontuação em quartis das análises realizadas em multiplex pelo sistema Plexor, foi percebido que o quartil superior apresentava ILD significativa pior do que a de pacientes nos demais quartis. Também foi observada uma estratificação do estadio clínico II em pior ou melhor prognóstico de acordo com o quartil de pontuação do teste de perfilamento proposto neste estudo; além disso, verificou-se que pacientes submetidas a tratamento neoadjuvante com pontuações inferiores tenderam a responder melhor à quimioterapia. CONCLUSÃO: Pelas características do comportamento evolutivo no presente estudo, HER2 parece ser melhor como possível biomarcador de células tumorais circulantes do que o CK-19. Até o presente momento do seguimento das pacientes incluídas neste estudo, não foi possível criar um modelo com diversas variáveis para prever o prognóstico de pacientes com câncer de mama. Isto ocorreu principalmente pelas características preditivas prognósticas superiores do perfilamento genético do tumor que desloca fatores de prognóstico tais como células circulantes e estadio clínico, expressão hormonal do tumor e idade de um modelo multivariado. Por outro lado, foi padronizada uma tecnologia genômica complexa que poderá viabilizar seu uso para a população se estudos posteriores confirmarem seu valor em outras coortes de pacientes com câncer de mama / BACKGROUND: According to the estimate of 2012 INCA, were expected 52,680 cases of breast cancer in Brazil, with an estimated risk of 52 cases per 100 000 women. These data show the need for effective identification of biomarkers for early screening and follow-up of these women during their treatment. In this work, for the evaluation of potential biomarkers of this disease, a model laboratory was designed to evaluate both the specific capacity of a given biomarker trace an initial breast tumor, as well as test its potential value for the follow-up of women already diagnosed during their treatment. This model was based on the evaluation of circulating tumor cells and tumor gene profiling. METHODS: Biological samples (peripheral blood and tumor) of 167 patients diagnosed with breast cancer stages I, II and III with an indication for adjuvant chemotherapy: a) to evaluate the presence of circulating tumor cells through the expression of HER2 and CK19 in Peripheral Blood Mononuclear fraction (PBMN) by quantitative RT-PCR and b) tumor profiling gene by analyzing the expression of 21 genes related to important processes of mammary carcinogenesis in paraffinized tissue samples by multiplex assay for quantitative RT-PCR using the Plexor ® System. RESULTS: Was observed a significant correlation between HER2 and CK19 in the first collection and decrease in concentration of HER2 in PB during the treatment, but were not perceived significant decrease of CK19 along the study. The expression of HER2 in the second collection of patients positive for HER2 in the first test tended to correlate with a significantly worse disease-free interval (DFI). Through standardization of the scores in quartiles of the analyzes performed at multiplex Plexor system was seen that the upper quartile ILD had significantly worse than patients in the other quartiles. Also stratification was observed in clinical stage II in better or worse prognosis according to quartiles of test score profiling proposed in this study, in addition, it was found that patients submitted to neoadjuvant treatment with lower scores tended to better respond to chemotherapy. CONCLUSION: HER2 seems to be better as possible biomarker of circulating tumor cells than the CK-19. So far the monitoring of patients included in this study, it was not possible to create a model with multiple variables to predict the prognosis of patients with breast cancer. This occurred primarily due to the characteristics predictive prognostic upper genetic profiling of tumor that displaces prognostic factors such as circulating cells and clinical stage, tumor hormone expression and age in a multivariate model. In the other hand, was standardized complex genomic technology that may enable their use for the population if further studies confirm its value in other cohorts of patients with breast cancer
133

An isotopic and historical study of diet and migration during the great Irish Potato Famine (1845-1852) : high-resolution carbon and nitrogen isotope profiling of teeth to investigate migration and short-term dietary change at the Union workhouse, Kilkenny and Lukin street, London

Beaumont, Julia January 2013 (has links)
Historical evidence from contemporary documents established that Irish migrants to London during the Great Irish Famine (1845-1852) were likely to come from low socio-economic groups in south-west Ireland, and has characterised mid-19th-century health status and living conditions in both locations. Using samples from 119 individuals from the Catholic cemetery at Lukin Street, London (1843-1854) and 20 from the Union Workhouse Famine cemetery, Kilkenny, Ireland (1847-51), mean bone collagen isotope values were established for the well-documented Irish pre-Famine potato-based diet (δ¹⁵N 10.6‰, δ¹³C -19.1‰), and the diet of contemporaneous Londoners (δ¹⁵N 12.6‰, δ¹³C -19.1‰). The introduction of maize as a short-term Famine relief food was identified in three Kilkenny juveniles with bone collagen δ¹³C above -17‰, and incremental dentine collagen demonstrating temporal changes in δ¹³C consistent with dietary change from C3 to C4 plants. Bone collagen values for two Lukin Street individuals were consistent with high marine protein consumption. Techniques developed in this study to sample increments of dentine representing nine months or less of life have improved temporal resolution not only for migration events but also short-term dietary changes and physiological status during childhood. Combining epigraphic, osteological and archaeological evidence, individual 'lifeways' have been constructed using isotope data and provide insights into the connection between health, diet and skeletal manifestations of deprivation during childhood and adolescence. New models are investigated for examining maternal and infant health using dentine collagen increments formed in utero and combining dentine and bone collagen values to explore the effects of nutritional stress on bone turnover.
134

Vibrational spectroscopy of keratin fibres : A forensic approach

Panayiotou, Helen January 2004 (has links)
Human hair profiling is an integral part of a forensic investigation but it is one of the most technically difficult subjects in forensic science. This thesis describes the research and development of a novel approach for the rapid identification of unknown human and other related keratin fibres found at a crime scene. The work presented here is developed systematically and considers sample collection, sample preparation, analysis and interpretation of spectral data for the profiling of hair fibres encountered in criminal cases. Spectral comparison of fibres was facilitated with the use of chemometrics methods such as PCA, SIMCA and Fuzzy Clustering, and the less common approach of multi-criteria decision making methodology (MCDM). The aim of the thesis was to investigate the potential of some vibrational spectroscopy techniques for matching and discrimination of single keratin hair fibres in the context of forensic evidence. The first objective (chapter 3) of the thesis was to evaluate the use of Raman and FT-IR micro-spectroscopy techniques for the forensic sampling of hair fibres and to propose the preferred technique for future forensic hair comparisons. The selection of the preferred technique was based on criteria such as spectral quality, ease of use, rapid analysis and universal application to different hair samples. FT-IR micro-spectroscopy was found to be the most appropriate technique for hair analysis because it enabled the rapid collection of spectra from a wide variety of hair fibres. Raman micro-spectroscopy, on the other hand, was hindered with fluorescence problems and did not allow the collection of spectra from pigmented fibres. This objective has therefore shown that FT-IR micro-spectroscopy is the preferable spectroscopic technique for forensic analysis of hair fibres, whilst Raman spectroscopy is the least preferred. The second objective (chapter 3) was to investigate, through a series of experiments, the effect of chemical treatment on the micro-environment of human hair fibres. The effect of bleaching agents on the hair fibres was studied with some detail at different treatment times and the results indicate a significant change in the chemical environment of the secondary structure of the hair fibre along with changes in the C-C backbone structure. One of the most important outcomes of this research was the behaviour of the fÑ-helix during chemical treatment. The hydrogen bonding in the fÑ-helix provides for the stable structure of the fibre and therefore any disruption to the fÑ-helix will inevitably damage the molecular structure of the fibre. The results highlighted the behaviour of the fÑ-helix, which undergoes a significant decrease in content during oxidation, and is partly converted to a random-coil structure, whilst the fÒ-sheet component of the secondary structure remains unaffected. The reported investigations show that the combination of FT-IR and Raman micro-spectroscopy can provide an insight and understanding into the complex chemical properties and reactions within a treated hair fibre. Importantly, this work demonstrates that with the aid of chemometrics, it is possible to investigate simultaneously FT-IR and Raman micro-spectroscopic information from oxidised hair fibres collected from one subject and treated at different times. The discrimination and matching of hair fibres on the basis of treatment has potential forensic applications. The third objective (chapter 4) attempted to expand the forensic application of FT-IR micro-spectroscopy to other keratin fibres. Animal fibres are commonly encountered in crime scenes and it thus becomes important to establish the origin of those fibres. The aim of this work was to establish the forensic applications of FT-IR micro-spectroscopy to animal fibres and to investigate any fundamental molecular differences between these fibres. The results established a discrimination between fibres consisting predominantly of fÑ-helix and those containing mainly a fÒ-sheet structure. More importantly, it was demonstrated through curve-fitting and chemometrics, that each keratin fibre contains a characteristic secondary structure arrangement. The work presented here is the first detailed FT-IR micro-spectroscopic study, utilising chemometrics as well as MCDM methods, for a wide range of keratin fibres, which are commonly, found as forensic evidence. Furthermore, it was demonstrated with the aid of the rank ordering MCDM methods PROMETHEE and GAIA, that it is possible to rank and discriminate keratin fibres according to their molecular characteristics obtained from direct measurements together with information sourced from the literature. The final objective (chapter 5) of the thesis was to propose an alternative method for the discrimination and matching of single scalp human hair fibres through the use of FT-IR micro-spectroscopy and chemometrics. The work successfully demonstrated, through a number of case scenarios, the application of the technique for the identification of variables such as gender and race for an unknown single hair fibre. In addition, it was also illustrated that known hair fibres (from the suspect or victim) can be readily matched to the unknown hair fibres found at the crime scene. This is the first time that a substantial, systematic FT-IR study of forensic hair identification has been presented. The research has shown that it is possible to model and correlate individual¡¦s characteristics with hair properties at molecular level with the use of chemometrics methods. A number of different, important forensic variables of immediate use to police in a crime scene investigation such as gender, race, treatment, black and white hair fibres were investigated. Blind samples were successfully applied both to validate available experimental data and extend the current database of experimental determinations. Protocols were posed for the application of this methodology in the future. The proposed FT-IR methodology presented in this thesis has provided an alternative approach to the characterisation of single scalp human hair fibres. The technique enables the rapid collection of spectra, followed by the objective analytical capabilities of chemometrics to successfully discriminate animal fibres, human hair fibres from different sources, treated from untreated hair fibres, as well as black and white hair fibres, on the basis of their molecular structure. The results can be readily produced and explained in the courts of law. Although the proposed relatively fast FT-IR technique is not aimed at displacing the two slower existing methods of hair analysis, namely comparative optical microscopy and DNA analysis, it has given a new dimension to the characterisation of hair fibres at a molecular level, providing a powerful tool for forensic investigations.
135

Estudo do perfilamento gênico tumoral e de marcadores de doença residual mínima (CK19 e c-ErbB-2) através de RT-PCR quantitativo na fração mononuclear do sangue periférico em pacientes com câncer de mama durante o tratamento / Study of tumor gene profiling and minimal residual disease markers (CK19 and c-ErbB-2) by quantitative RT-PCR in peripheral blood mononuclear fraction in patients with breast cancer during chemotherapy

Renata Kelly Kuniyoshi 13 November 2013 (has links)
INTRODUÇÃO: De acordo com a estimativa de 2012 do INCA, eram esperados 52.680 novos casos de câncer de mama no Brasil, com um risco estimado de 52 casos a cada 100 mil mulheres. Estes dados mostram a necessidade da identificação de biomarcadores efetivos para rastreamento precoce e seguimento destas mulheres durante seu tratamento. Neste trabalho, para a avaliação de potenciais biomarcadores desta doença, foi idealizado um modelo laboratorial específico que avalie tanto a capacidade de um dado biomarcador rastrear um tumor inicial de mama, bem como testar o seu potencial valor para o seguimento de mulheres já diagnosticadas durante seu tratamento. Este modelo baseia-se na avaliação de células tumorais circulantes e perfilamento gênico tumoral. MÉTODOS: Amostras biológicas (sangue periférico e tumor) de 167 pacientes diagnosticadas com carcinoma mamário estadios I, II e III com indicação de quimioterapia adjuvante para: a) avaliação da presença de células tumorais circulantes através da expressão de CK19 e HER2 na Fração Mononuclear do Sangue Periférico (FMNSP) por RT-PCR quantitativo e b) perfilamento gênico tumoral através da análise da expressão de 21 genes relacionados a importantes processos de carcinogênese mamária em amostras de tecido parafinado por ensaio multiplex de RT-PCR quantitativo utilizando o sistema Plexor®. RESULTADOS: Foi observada uma correlação significativa entre CK19 e HER2 na primeira coleta e queda da concentração de HER2 no SP durante o tratamento; porém, não foi percebida queda significativa do CK19 ao longo do estudo. A expressão de HER2 na segunda coleta de pacientes positivas para HER2 na primeira coleta tendeu a se correlacionar significativamente com um pior Intervalo Livre de Doença (ILD). Através da padronização da pontuação em quartis das análises realizadas em multiplex pelo sistema Plexor, foi percebido que o quartil superior apresentava ILD significativa pior do que a de pacientes nos demais quartis. Também foi observada uma estratificação do estadio clínico II em pior ou melhor prognóstico de acordo com o quartil de pontuação do teste de perfilamento proposto neste estudo; além disso, verificou-se que pacientes submetidas a tratamento neoadjuvante com pontuações inferiores tenderam a responder melhor à quimioterapia. CONCLUSÃO: Pelas características do comportamento evolutivo no presente estudo, HER2 parece ser melhor como possível biomarcador de células tumorais circulantes do que o CK-19. Até o presente momento do seguimento das pacientes incluídas neste estudo, não foi possível criar um modelo com diversas variáveis para prever o prognóstico de pacientes com câncer de mama. Isto ocorreu principalmente pelas características preditivas prognósticas superiores do perfilamento genético do tumor que desloca fatores de prognóstico tais como células circulantes e estadio clínico, expressão hormonal do tumor e idade de um modelo multivariado. Por outro lado, foi padronizada uma tecnologia genômica complexa que poderá viabilizar seu uso para a população se estudos posteriores confirmarem seu valor em outras coortes de pacientes com câncer de mama / BACKGROUND: According to the estimate of 2012 INCA, were expected 52,680 cases of breast cancer in Brazil, with an estimated risk of 52 cases per 100 000 women. These data show the need for effective identification of biomarkers for early screening and follow-up of these women during their treatment. In this work, for the evaluation of potential biomarkers of this disease, a model laboratory was designed to evaluate both the specific capacity of a given biomarker trace an initial breast tumor, as well as test its potential value for the follow-up of women already diagnosed during their treatment. This model was based on the evaluation of circulating tumor cells and tumor gene profiling. METHODS: Biological samples (peripheral blood and tumor) of 167 patients diagnosed with breast cancer stages I, II and III with an indication for adjuvant chemotherapy: a) to evaluate the presence of circulating tumor cells through the expression of HER2 and CK19 in Peripheral Blood Mononuclear fraction (PBMN) by quantitative RT-PCR and b) tumor profiling gene by analyzing the expression of 21 genes related to important processes of mammary carcinogenesis in paraffinized tissue samples by multiplex assay for quantitative RT-PCR using the Plexor ® System. RESULTS: Was observed a significant correlation between HER2 and CK19 in the first collection and decrease in concentration of HER2 in PB during the treatment, but were not perceived significant decrease of CK19 along the study. The expression of HER2 in the second collection of patients positive for HER2 in the first test tended to correlate with a significantly worse disease-free interval (DFI). Through standardization of the scores in quartiles of the analyzes performed at multiplex Plexor system was seen that the upper quartile ILD had significantly worse than patients in the other quartiles. Also stratification was observed in clinical stage II in better or worse prognosis according to quartiles of test score profiling proposed in this study, in addition, it was found that patients submitted to neoadjuvant treatment with lower scores tended to better respond to chemotherapy. CONCLUSION: HER2 seems to be better as possible biomarker of circulating tumor cells than the CK-19. So far the monitoring of patients included in this study, it was not possible to create a model with multiple variables to predict the prognosis of patients with breast cancer. This occurred primarily due to the characteristics predictive prognostic upper genetic profiling of tumor that displaces prognostic factors such as circulating cells and clinical stage, tumor hormone expression and age in a multivariate model. In the other hand, was standardized complex genomic technology that may enable their use for the population if further studies confirm its value in other cohorts of patients with breast cancer
136

Novas funções da proteina AIRE : 1) seu papel na resposta mediada por dectina-1 em fagocitos mononucleares humanos. 2) sua associação com a queratina 17, proteina dos filamentos intermediarios / New roles of AIRE protein : 1) AIRE role in Dection-1 mediated patway in human mononuclear phagocytes and 2) AIRE association with keratin-17, a component of intermediate filaments

Talero, Luis Alberto Pedroza 13 August 2018 (has links)
Orientador: Antonio Condino Neto / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-13T22:05:12Z (GMT). No. of bitstreams: 1 Talero_LuisAlbertoPedroza_D.pdf: 1538530 bytes, checksum: 6dc94ec71cdd6f03d096be015a2b1757 (MD5) Previous issue date: 2009 / Resumo: A Poliendocrinopatia autoimune associada a candidíase e distrofia ectodérmica (APECED) é um síndrome caracterizado pela presença de pelo menos dois sintomas clínicos, endocrinopatia autoimune, sendo que as mais comuns são hipoparatiroidismo, doença de Addison, além de candidíase mucocutânea crônica. É também comum nos pacientes o desenvolvimento de distrofia ectodérmica, como distrofia nas unhas ou alopécia. O APECED é produzido por mutações no gene AIRE, que codifica uma proteína com propriedades reguladoras na transcrição de proteínas ectópicas no timo, o que estaria envolvido na seleção negativa de células T auto-reativas, e conseqüentemente no desenvolvimento da doença autoimune. No entanto a associação da deficiência da proteína AIRE com a suscetibilidade a candidíase ou a distrofia ectodérmica permanecem obscuras. No presente trabalho, investigamos a possibilidade que esta associação esteja envolvida com a expressão e função da proteína AIRE no ambiente extra-tímico. Usando células de sangue periférico de pacientes com mutações no AIRE, e a técnica de SiRNA para silenciar este gene em células de linhagem mielomonocítica THP-1, demonstramos que a proteína AIRE é importante para a resposta via KF-kB dos TLRs e Dectina-1, sendo que AIRE está presente num complexo com Dectina-1, Syk e Card-9, formado após o estímulo com Curdlan. Além disso demonstramos que a formação deste complexo pode acontecer no citoplasma ou membrana citoplasmática, uma vez que após este estímulo, a proteína AIRE é exportada do núcleo permanecendo temporariamente na membrana. Finalmente usando a técnica de espectroscopia de massa e microscopia confocal, mostramos que AIRE interage com a proteína Queratina 17, tanto em células THP-1 como em células HaCaT (linhagem de queratinócitos), quando as células entram num estágio de espraiamento e migração. Assim, a presença da proteína AIRE na via de sinalização da Dectina-1, pode estar relacionada com a susceptibilidade a infecções crônicas por C. albicans observada nestes pacientes. A resposta imune via Dectina-1 é importante na resposta a este fungo e defeitos na molécula CARD9 e Dectina-1 podem estar associados a Candidíase mucocutânea crônica. Por outro lado, a descrição da associação de AIRE com K17 pode ser relevante, já que pacientes com mutações no gene que codifica para a proteína K17 desenvolvem uma doença chamada paquioníquia congênita, caracterizada por distrofia das unhas e alopécia, características clínicas observadas também nos pacientes com APECED. Deste modo, neste trabalho apresentamos evidências que apontam para um novo papel funcional da proteína AIRE no ambiente extratímico, que poderia explicar em parte algumas características clínicas dos pacientes com APECED, como a elevada suscetibilidade a infecções por C. albicans, e a distrofia ectodérmica / Abstract: The autoimmune polyendocrinopathy candidiasis and ectodermal dystrophy (APECED) is characterized by the presence of two from three major clinical symptoms: Addison's disease, and/or hypoparathyroidism, and/or chronic mucocutaneous candidiasis. These patients develop also ectodermal dystrophies like nail dystrophy and alopecia. APECED is caused by mutations in the autoimmune regulator gene (AIRE). This gene encodes a protein with DNA binding capacity that can transcriptionally modulate ectopic peripheral tissue antigen (PTA) expression in the thymus, facilitating T cell negative selection. Defects in AIRE may be related with the development of multipleendocrine failure of autoimmune origin in patients with APECED. In spite of this, the role of AIRE deficiency in the C. albicans susceptibility or ectodermal dystrophy, common features in APECED patients, remains to be elucidated. In the present work we explored the hypothesis that candidiasis and ectodermal dystrophy are associated with the extra-thymic role of AIRE. For this we used peripheral blood mononuclear cells from APECED patients, and also THP-1 cells treated with SiRNA for AIRE gene to obtain AIRE deficient cells. We demonstrated that AIRE is required for Dectin-1- and TLR-ligand-induced inflammatory response and complexes with Dectin-1, Syk, and CARD9 after Curdlan stimulation. In addition, we showed that this complex formation takes place outside the nucleus, once that after Curdlan stimulation AIRE seems to be exported to the cytoplasm and transiently locate at the cytoplasmic membrane. Finally using mass spectra and confocal microscopy, we showed an interaction between AIRE and the intermediate filament protein Keratin-17, in both THP-1 cells and the keratinocyte cell line HaCaT. Therefore, the presence of AIRE protein in Dectin-1 pathway seems to be important on the C. albicans response, and the absence of this protein could be a risk factor important for developing candidiasis, commonly observed in APECED patients. This observation is supported by the fact that Dectin-1 is important for C albicans response, and also the recently description of mutations in Dectin-1 and CARD9 and its association with chronic mucocutaneous candidiasis. On the other hand, the description of AIRE and K17 association is important, since patients with defects on K17 gene develop congenital pachyonychia, a disease characterized by nail dystrophy and alopecia, also observed in APECED patients. Thus we provided evidence for a new role of AIRE protein in the extrathymic environment, which in may explain, at least in part, some of the common clinical features other than autoimmunity, observed in APECED patients / Doutorado / Saude da Criança e do Adolescente / Doutor em Saude da Criança e do Adolescente
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Expressão de genes de repressão gênica em tumor primário em relação à presença ou ausência de células metastáticas ocultas na medula óssea em pacientes com câncer de mama / Expression of genes involved in transcriptional repression in the primary tumor of breast cancer patients in the presence or absence of occult metastatic cells in the bone marrow

Ana Paula Santana de Abreu 25 August 2006 (has links)
Estudos sugerem que a presença de células metastáticas ocultas em medula óssea pode ser fator prognóstico em câncer de mama. Além disso, é possível que um perfil gênico tumoral específico, caracterizado por repressão da expressão gênica, esteja associado à detecção de células tumorais na medula óssea. O silenciamento de genes é controlado pela desacetilação de histonas e metilação de DNA, esta última catalisada por enzimas DNA metil transferases. Outro alvo de metil-transferases são as histonas, e histona H3 quando sofre metilação em lisina 9, gera sítio de ligação a proteínas HP1 (Heterocromatin protein-1 ou cromobox). Membros da família HP1 (HP1Hsalfa, HP1Hsbeta e HP1HsY) participam da formação da heterocromatina e da regulação da expressão de genes. Logo, nosso objetivo foi determinar no tumor primário de mama, a expressão de HP1Hsalfa, HP1Hsbeta e HP1Hsy , que participam da repressão gênica, em relação à presença ou ausência de células metastáticas ocultas na medula óssea. Neste estudo foram incluídas 37 pacientes de forma prospectiva, atendidas no Instituto Brasileiro de Controle do Câncer (IBCC) no período de junho de 2004 a julho de 2005, com diagnóstico histopatológico de carcinoma invasivo de mama, estádio clínico (EC) I (16,2%), II (51,4%) ou III (32,4%), segundo a classificação patológica. A idade mediana das pacientes foi 63 anos (41 a 90) e 62.2% delas encontravam-se na pós-menopausa, sendo que 24.3% relatava história familiar para câncer de mama. O tipo histológico predominante foi carcinoma ductal invasivo (89.2% dos casos), sendo, o restante, representado por carcinoma lobular invasivo (10.8%). Foram coletadas amostras de tumor primário de mama e de aspirado de medula óssea de cada paciente. A presença de células metastáticas ocultas (CMO) na medula óssea (MO) foi detectada através da expressão de citoqueratina 19 (CK19) pelo método de nested RT-PCR. A expressão relativa dos genes HP1Hsalfa, HP1Hsbeta e HP1Hsy foi determinada no tumor primário, usando-se a técnica de RT-PCR em tempo real. Presença de CMO foi detectada na MO de 20 pacientes (54.1%). Não observamos diferença na expressão de HP1Hs? (1,93 ± 2,25 MO- vs 3,84 ± 5,53 MO+), HP1Hs? (6,74 ± 6,31 MO- vs 6,49 ± 5,86 MO+) e HP1Hs? (24,58 ± 11,14 MO- vs 24,91 ± 15,88 MO+) entre as amostras tumorais de pacientes com presença (MO+) ou ausência (MO-) de micrometástase medular. Também não observamos variação da expressão de genes HP1 em relação ao comprometimento linfonodal, dimensão e grau histológico do tumor, expressão tumoral de receptores de estrógeno e estado menopausal da paciente. A expressão de HP1Hsalfa em tumores de pacientes com câncer de mama ERBB2 negativos, entretanto, foi maior do que em tumores ERBB2 positivos. Nossos dados indicam que em tumores de mama, a expressão de HP1Hsalfa, HP1Hsbeta e HP1Hsy não parece se associar à presença de células ocultas em medula óssea / Studies suggest that the presence of occult metastatic cells (OMC) in the bone marrow (BM) may be a prognostic factor in breast cancer. Besides, it is possible that a specific tumor gene profile, characterized by repression of gene expression, may be associated to the presence of tumoral cells in the bone marrow. Gene silencing is controlled by histone deacetylation and DNA methylation, the last one catalized by enzymes DNA methyltransferases (DNMTs). Histones are another target of methyltransferases, and methylation of histone H3 on lysine-9 generate a binding site for HP1 proteins (Heterocromatin protein-1 or chromobox). Members of the HP1 family (HP1Hsalfa, HP1Hsbeta e HP1Hsy) take part in heterochromatin formation and gene expression regulation. Hence, our aim was to determine in the primary tumor of the breast, the expression of HP1Hsalfa, HP1Hsbeta e HP1Hsy, which participate in gene repression, in the presence or absence of occult metastatic cells in the bone marrow. In this study, 37 patients treated at Instituto Brasileiro de Controle do Câncer, from June 2004 to July 2005, with invasive breast cancer histopathologically confirmed, pathological clinical stages I (16,2%), II (51,4%) or III (32,4), were included. The median age of the patients was 63 years (41 to 90), 62.2% were post-menopausal and 24.3% reported family history of breast cancer. Invasive ductal carcinoma was diagnosed in most patients (89.2%), and invasive lobular carcinoma was detected in the other patients (10.8%). Tumor samples and bone marrow aspirates were obtained from each patient. The presence of CMO in BM was detected by keratin-19 (CK19) expression by nested RT-PCR. The relative expression of the genes HP1Hsalfa, HP1Hsbeta e HP1Hsy was determined by real-time RT-PCR. Occult metastatic cells (OMC) in BM were detected in 20 patients (54.1%). No differences were observed in the expression of HP1Hs? (1,93 ± 2,25 BM- vs 3,84 ± 5,53 BM+), HP1Hsalfa (6,74 ± 6,31 BM- vs 6,49 ± 5,86 BM+) and HP1Hsbeta (24,58 ± 11,14 BM- vs 24,91 ± 15,88 BM+) between tumor samples of BM+ patients and BM- patients. Variations of HP1 gene expression were neither observed according to lymph node involvement, tumor size, histological grade, estrogen receptor status and menopausal status. However, HP1Hsbeta expression in ERBB2-negative tumors was higher than in ERBB2-positive tumors. Our data indicate that in breast cancer tumors, expression of HP1Hsalfa, HP1Hsbeta e HP1Hsy does not seem to be associated with the presence of occult metastatic cells in the bone marrow
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Expressão gênica diferencial das células estromais obtidas de medula óssea na presença ou ausência de célula tumoral oculta em pacientes com câncer de mama / Differential gene expression of bone marrow stromal cells from breast cancer patients in the presence or abscence of occult tumor cells

Cintia Milani 21 September 2006 (has links)
A célula estromal pode influenciar o desenvolvimento do tumor no sítio primário e secundário, mas pouco é conhecido sobre as características moleculares das células estromais presentes na medula óssea de pacientes com câncer de mama. Nosso objetivo foi avaliar a expressão gênica diferencial entre as células estromais oriundas de medula óssea na presença ou ausência de célula tumoral oculta. Coletamos dez aspirados de medula óssea das pacientes com câncer de mama. A classificação do comprometimento da medula por células tumorais ocultas foi realizada pela detecção da expressão de CK19 por Nested-RT-PCR e quatro entre dez pacientes apresentaram presença de célula tumoral na medula óssea. Estabelecemos culturas primárias de células estromais de todas as amostras e, selecionamos amostras originárias de duas pacientes contendo linfonodos comprometidos e presença de célula tumoral oculta em medula e também de duas pacientes que não apresentavam linfonodos comprometidos e nem célula tumoral oculta na medula. As pacientes selecionadas eram pós-menopausadas com diagnóstico de carcinoma ductal invasor e expressão imunohistoquímica positiva para receptor de estrógeno e progesterona. Realizamos avaliação do perfil de expressão gênica entre estes dois grupos, o que nos revelou 21 genes diferencialmente expressos dentre os 4.608 genes imobilizados em lâmina de cDNA microarray; nove genes hiperexpressos em célula estromal de medula comprometida (PTHLH, TLOC1, NCOA6, C17orf57, ANAPC11, MAST4, POLR3E, CPNE1 e B4GALT5) e doze genes hipoexpressos em célula estromal de medula comprometida (MRPL2, NAT10, DAP, RNF2, FLOT2, FKBP10, SLIT3, EBNA1BP2, SLC35B2, MICAL2, GPR3, TSPAN17). Nossos dados sugerem que apesar da expressão gênica de células estromais oriundas de medula óssea comprometida ou não por micrometástases ser semelhante, algumas diferenças podem ser identificadas. / Stromal cells may influence tumor development in primary and secundary sites, however, molecular characteristics of bone marrow stromal cells from breast cancer patients are almost unknown. Our aim was to evaluate the differential gene expression of bone marrow stromal cells from breast cancer patients in the presence or abscence of occult tumor cells. Bone marrow (BM) aspirates were obtained from 10 breast cancer patients. The presence of occult bone marrow disseminated tumor cells was detected by CK19 expression quantified by reverse transcriptase polymerase chain reaction (RT-PCR). Presence of tumoral cell was detected in four of ten BM samples. Stromal cells primary cultures were established and samples from two patients with positive lymph nodes and presence of occult tumor cells in bone marrow and samples from two patients with negative lymph nodes and abscence of occult tumor cells in bone marrow were selected. All the included patients were postmenopausal with invasive ductal carcinoma and positive estrogen and progesterone receptors detected by immunohistochemical analysis. Gene profile evaluated in cDNA microarray slides containing 4.608 spotted genes revealed 21 differencially expressed genes, nine upregulated (PTHLH, TLOC1, NCOA6, C17orf57, ANAPC11, MAST4, POLR3E, CPNE1 e B4GALT5) and twelve downregulated (MRPL2, NAT10, DAP, RNF2, FLOT2, FKBP10, SLIT3, EBNA1BP2, SLC35B2, MICAL2, GPR3, TSPAN17) in stromal cell derived from bone marrow in the presence of tumor breast cancer cell. Our data suggest that gene expression from bone marrow derived stromall cells in the presence or abscence of occult tumor cells seems similar, however small differences may be identified.
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Archéo-biogéochimie isotopique, reconstitutions des régimes alimentaires et des schémas de mobilité, et interactions bioculturelles. Les sépultures plurielles de la catacombe des Saints Pierre-et-Marcellin (Rome, Ier-IIIe s. ap. J.-C.) : Les sépultures plurielles de la région X de la catacombe des Saints Pierre-et-Marcellin (Rome, Ier-IIIe s. ap. J.-C.) / Isotopic archeo-biogeochemistry, reconstitution of diet and patterns of mobility, bio-cultural interactions : the plural burials of the region X of the catacomb of Saints Peter and Marcellinus (Rome, 1st-3rd cent. AD) / Archeobiochimica isotopica, ricostituzione dei regimi alimentari e degli schemi di mobilità, e interazioni bio-culturali : le sepolture plurime della regione X della catacomba dei Santi Pietro e Marcellino (Roma, I-III sec. D. C.)

Salesse, Kevin 17 December 2015 (has links)
Entre 2003 et 2010, dans la région centrale nommée X de la catacombe des Saints Pierre-et-Marcellin à Rome, a été découvert et en partie fouillé un ensemble de sépultures plurielles inédites (Ier-IIIe s. ap. J.-C.) contenant plusieurs centaines d’individus, lesquels ont été inhumés selon des pratiques funéraires singulières à la suite d’un épisode de surmortalité de nature probablement épidémique. Pour appréhender l’histoire de vie (alimentation et mobilité) de ces défunts et rediscuter sur la base d’éléments nouveaux certaines hypothèses préalablement établies, nous avons mené dans le cadre de ce travail une approche archéo-biogéochimique multi-proxy (14C, δ13C, δ15N, δ18O et 87Sr/86Sr) et multi-tissulaire (émail, os, cheveu) sur un échantillon de 130 individus issus de six différentes chambres. Nous avons dans un premier temps vérifié l’intégrité biochimique et isotopique des fractions minérales (phases carbonatées) et organiques (phases collagénique et kératinique) des échantillons à partir d’indicateurs classiques mesurés en routine (%Col, %C, %N, C/N, PCO2 et PCO2/Masse) et par spectroscopie IRTF (IRSF, CO3/PO4 et AmideI/PO4) et par une approche innovante consistant en des datations 14C sur couples collagène-apatite pour valider le signal isotopique des fractions minérales. Nos résultats mettent en évidence des différences extrêmes de préservation de toutes les phases. La trajectoire diagénétique des échantillons n’est toutefois pas aléatoire mais dépendante des conditions environnementales et taphonomiques différant entre les petites et les grandes chambres. En outre, nous avons pu démontrer qu’en dépit de fortes recristallisations et d’échanges isotopiques avec l’environnement sépulcral, les phases carbonatées possèdent un signal isotopique biogénique non altéré. Nous avons dans un second temps reconstruit les régimes alimentaires des individus en nous appuyant sur des référentiels de comparaisons robustes ainsi que divers modèles interprétatifs (mono-proxys versus multi-proxys ; qualitatifs versus quantitatifs), lesquels ont été dans certains cas adaptés au besoin de notre étude. D’une façon générale, nos résultats montrent que l’essentiel des individus a eu accès à un régime alimentaire type fondé sur la triade Céréales C3/Viande C3/Poisson marin. Ce régime alimentaire type n’est toutefois pas exclusif, certains individus (n = 13) ayant consommé de façon occasionnelle d’autres catégories de ressources tels que du poisson dulcicole ou des céréales C4. Nos résultats révèlent que les changements d’alimentation au cours de la vie sont relativement limités. Par ailleurs, cette population se singularise sur un plan strictement alimentaire au regard des autres populations contemporaines romaines pour lesquelles des valeurs isotopiques sont publiées. Nous avons dans un troisième temps étudié les schémas de mobilité des individus en nous fondant sur une approche rigoureuse de nos données et sur des référentiels de comparaison les plus exhaustifs possible ainsi qu’en tenant compte de biais ordinairement éludés (faits culturels, influence du climat et erreurs associées aux équations de conversion). Nos résultats mettent en lumière qu’a minima 23 % (n = 30) des individus étudiés sont migrants. Ces derniers ne se distinguent toutefois pas de par leur alimentation des résidents romains. Nous avons pu montrer en outre que ces migrants ont eu des trajectoires de vie complexes et hétérogènes et que trois schémas de mobilité distincts les caractérisent. Notre population ne se différencie pas en termes de taux de migrants des autres populations romaines pour lesquelles des données isotopiques sont disponibles. Elle se distingue en revanche par son cosmopolitisme avec des origines pour les migrants des plus diverses : Europe, Afrique, Arabie et Asie mineure [...]. / An assembly of unpublished complex plural burials (1st-3rd cent. AD.) was discovered and partially excavated, between 2003 and 2010 in the central region called X of the catacomb of Saints Peter and Marcellinus in Rome. It contains several hundred individuals which were buried according to uncommon funeral practices following a mortality episode of likely epidemic nature. To understand the life history (diet and mobility patterns) of these deceased and to discuss again certain assumptions previously established on the basis of new evidences, we have as part of this work conducted an archaeo-biogeochemical multi-proxy (14C, δ13C, δ15N, δ18O et 87Sr/86Sr) and multi-tissue (enamel, bones, hair) approach on a sub-sample of 130 individuals coming from six different chambers. At the outset, we tested the biochemical and isotopic integrity of mineral (carbonate phases) and organic fractions (collagen and keratin phases) samples from conventional indicators measured in routine (%Col, %C, %N, C/N, PCO2 et PCO2/Mass), by FTIR spectroscopy (IRSF, CO3/PO4 and AmideI/PO4) and by an innovative approach consisting of 14C dating on collagen-apatite to validate the isotopic signal of mineral fractions. Our results highlight extreme differences of preservation of all phases. Diagenetic trajectory of samples is however not random but dependent on environmental and taphonomical conditions which differ between small and large chambers. Furthermore, we have been able to demonstrate that, despite strong recrystallization and isotopic exchanges with the sepulchral environment, carbonated phases have an unaltered biogenic isotopic signal. Secondly, we rebuilt the diets of individuals based on robust comparisons repositories and various interpretative models (mono-proxy versus multi-proxies; qualitative versus quantitative) which were, in some cases, adapted to the needs of our study. In general, our results show that most of the individuals had access to such a type diet based on the triad Cereals C3/Meat C3/Marine fish. This type diet would however not be exclusive, some individuals (n = 13) would have indeed occasionally consumed other resources such as freshwater fish or C4 cereals. Our results indicate that changes of diet during the life history are relatively limited. Besides, with regard to consumed food, this population is distinguished from other contemporary Roman populations for whom isotopic values are published. In the third place, we studied individual’s mobility patterns based on a rigorous approach to our data and on a comparison of the most comprehensive repositories as possible with taking into account the bias usually evaded (cultural facts, influence of climate and errors associated with conversion equations). Our results highlight that a minimum of 23% (n = 30) of the studied individuals are migrants. These, however, are not distinguished from Roman residents through their diet. We were able to show further that these migrants had complex and heterogeneous trajectories during their life within three distinct mobility patterns characterizing them. In terms of migrant’s rates, our population does not differ from other Roman populations for which the isotopic data are available. It differs however by its cosmopolitanism with origins for more diverse migrants: Europe, Africa, Arabia and Asia Minor [...]. / Tra il 2003 e il 2010, nella regione centrale chiamata X della catacomba dei Santi Pietro e Marcellino a Roma, è stato scoperto e parzialmente scavato un insieme di sepolture plurime inedite (I-III sec. D.C.) contenente diverse centinaia di individui, i quali sono stati inumati secondo le pratiche funerarie singolari in seguito ad un episodio di sovramortalità di natura probabilmente epidemica. Per comprendere la storia di vita (alimentazione e mobilità) di questi defunti e ridiscutere, sulla base di nuovi elementi, alcune ipotesi precedentemente formulate, abbiamo condotto, nel quadro di questo lavoro, un approccio archeo-biogeochimico multi-proxys (14C, δ13C, δ15N, δ18O e 87Sr/86Sr) e multi-tessuto (smalto, ossa, capelli) su un campione di 130 individui da sei stanze diverse. Abbiamo inizialmente verificato l'integrità biochimica e isotopica delle frazioni minerali (fasi carbonatiche) ed organiche (fasi collageniche e cheratiniche) dei campioni provenienti da indicatori classici misurati in routine (%Col, %C, %N, C/N, PCO2 e PCO2/Massa) e per spettroscopia FTIR (IRSF, CO3/PO4 e AmmideI/PO4) ed un approccio innovativo costituito da datazione 14C su coppie collagene-apatite per validare il segnale isotopico delle frazioni minerali. I nostri risultati mettono in evidenza delle differenze estreme di preservazione di tutte le fasi. La traiettoria diagenetica dei campioni non è però aleatoria, ma dipendente dalle condizioni ambientali e tafonomiche che differiscono tra camere piccole e grandi. Inoltre, abbiamo potuto dimostrare che nonostante delle forti ricristallizzazioni e degli scambi isotopici con l'ambiente sepolcrale, le fasi carbonatiche hanno un segnale isotopico biogenetico inalterato. Abbiamo in un secondo tempo ricostruito i regimi alimentari degli individui basandoci su riferimenti di confronto robusti e vari modelli interpretativi (mono-proxys versus multi-proxys, qualitativi versus quantitativi), i quali sono stati in alcuni casi, adattati alle esigenze del nostro studio. In generale, i nostri risultati mostrano che la maggior parte degli individui ha avuto accesso ad un regime alimentare tipo basato sulla triade Cereali C3/Carne C3/Pesci marini. Questo regime alimentare non è tuttavia esclusivo, avendo certi individui (n = 13) consumato casualmente altre categorie di risorse come il pesce dulciacquicolo o dei cereali C4. I nostri risultati indicano che i cambiamenti di alimentazione nel corso della vita sono relativamente limitati. Inoltre, questa popolazione si distingue da un piano strettamente alimentare rispetto alle altre popolazioni contemporanee romane per le quali dei valori isotopici sono pubblicati. Abbiamo in un terzo tempo studiato gli schemi di mobilità degli individui basandoci su un approccio rigoroso dei nostri dati e su riferimenti di confronto i più esaustivi possibile, e anche tenendo conto di punti di vista solitamente elusi (fatti culturali, influenza del clima e errori associati alle equazioni di conversione). I nostri risultati mettono in luce che a minima 23% (n = 30) degli individui studiati sono migranti. Questi ultimi, tuttavia, non si distinguono per la loro alimentazione dai residenti romani. Abbiamo potuto mostrare, inoltre, che questi migranti hanno avuto percorsi di vita complessi ed eterogenei e che tre schemi di mobilità distinti li caratterizzano. Nostra popolazione non si differenzia in termini di tasso di migranti da altre popolazioni romane per le quali sono disponibili dei dati isotopici. Essa si distingue tuttavia per il suo cosmopolitismo con delle origini per i migranti delle più diverse: Europa, Africa, Arabia e Asia Minore [...].
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Ecological and Physiological Effects of Proximity to Roads in Eastern Box Turtles (<i>Terrapene carolina carolina</i>)

Weigand, Nicole Marcel 01 October 2018 (has links)
No description available.

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