992 resultados para Ester-dermasan.
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Background: In Catalonia (Spain) breast cancer mortality has declined since the beginning of the 1990s. The dissemination of early detection by mammography and the introduction of adjuvant treatments are among the possible causes of this decrease, and both were almost coincident in time. Thus, understanding how these procedures were incorporated into use in the general population and in women diagnosed with breast cancer is very important for assessing their contribution to the reduction in breast cancer mortality. In this work we have modeled the dissemination of periodic mammography and described repeat mammography behavior in Catalonia from 1975 to 2006. Methods: Cross-sectional data from three Catalan Health Surveys for the calendar years 1994, 2002 and 2006 was used. The dissemination of mammography by birth cohort was modeled using a mixed effects model and repeat mammography behavior was described by age and survey year. Results: For women born from 1938 to 1952, mammography clearly had a period effect, meaning that they started to have periodic mammograms at the same calendar years but at different ages. The age at which approximately 50% of the women were receiving periodic mammograms went from 57.8 years of age for women born in 1938–1942 to 37.3 years of age for women born in 1963–1967. Women in all age groups experienced an increase in periodic mammography use over time, although women in the 50–69 age group have experienced the highest increase. Currently, the target population of the Catalan Breast Cancer Screening Program, 50–69 years of age, is the group that self-reports the highest utilization of periodic mammograms, followed by the 40–49 age group. A higher proportion of women of all age groups have annual mammograms rather than biennial or irregular ones. Conclusion: Mammography in Catalonia became more widely implemented during the 1990s. We estimated when cohorts initiated periodic mammograms and how frequently women are receiving them. These two pieces of information will be entered into a cost-effectiveness model of early detection in Catalonia.
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Background: During the last part of the 1990s the chance of surviving breast cancer increased. Changes in survival functions reflect a mixture of effects. Both, the introduction of adjuvant treatments and early screening with mammography played a role in the decline in mortality. Evaluating the contribution of these interventions using mathematical models requires survival functions before and after their introduction. Furthermore, required survival functions may be different by age groups and are related to disease stage at diagnosis. Sometimes detailed information is not available, as was the case for the region of Catalonia (Spain). Then one may derive the functions using information from other geographical areas. This work presents the methodology used to estimate age- and stage-specific Catalan breast cancer survival functions from scarce Catalan survival data by adapting the age- and stage-specific US functions. Methods: Cubic splines were used to smooth data and obtain continuous hazard rate functions. After, we fitted a Poisson model to derive hazard ratios. The model included time as a covariate. Then the hazard ratios were applied to US survival functions detailed by age and stage to obtain Catalan estimations. Results: We started estimating the hazard ratios for Catalonia versus the USA before and after the introduction of screening. The hazard ratios were then multiplied by the age- and stage-specific breast cancer hazard rates from the USA to obtain the Catalan hazard rates. We also compared breast cancer survival in Catalonia and the USA in two time periods, before cancer control interventions (USA 1975–79, Catalonia 1980–89) and after (USA and Catalonia 1990–2001). Survival in Catalonia in the 1980–89 period was worse than in the USA during 1975–79, but the differences disappeared in 1990–2001. Conclusion: Our results suggest that access to better treatments and quality of care contributed to large improvements in survival in Catalonia. On the other hand, we obtained detailed breast cancer survival functions that will be used for modeling the effect of screening and adjuvant treatments in Catalonia.
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Background: At present, it is complicated to use screening trials to determine the optimal age intervals and periodicities of breast cancer early detection. Mathematical models are an alternative that has been widely used. The aim of this study was to estimate the effect of different breast cancer early detection strategies in Catalonia (Spain), in terms of breast cancer mortality reduction (MR) and years of life gained (YLG), using the stochastic models developed by Lee and Zelen (LZ). Methods: We used the LZ model to estimate the cumulative probability of death for a cohort exposed to different screening strategies after T years of follow-up. We also obtained the cumulative probability of death for a cohort with no screening. These probabilities were used to estimate the possible breast cancer MR and YLG by age, period and cohort of birth. The inputs of the model were: incidence of, mortality from and survival after breast cancer, mortality from other causes, distribution of breast cancer stages at diagnosis and sensitivity of mammography. The outputs were relative breast cancer MR and YLG. Results: Relative breast cancer MR varied from 20% for biennial exams in the 50 to 69 age interval to 30% for annual exams in the 40 to 74 age interval. When strategies differ in periodicity but not in the age interval of exams, biennial screening achieved almost 80% of the annual screening MR. In contrast to MR, the effect on YLG of extending screening from 69 to 74 years of age was smaller than the effect of extending the screening from 50 to 45 or 40 years. Conclusion: In this study we have obtained a measure of the effect of breast cancer screening in terms of mortality and years of life gained. The Lee and Zelen mathematical models have been very useful for assessing the impact of different modalities of early detection on MR and YLG in Catalonia (Spain).
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Background: Model organisms are used for research because they provide a framework on which to develop and optimize methods that facilitate and standardize analysis. Such organisms should be representative of the living beings for which they are to serve as proxy. However, in practice, a model organism is often selected ad hoc, and without considering its representativeness, because a systematic and rational method to include this consideration in the selection process is still lacking. Methodology/Principal Findings: In this work we propose such a method and apply it in a pilot study of strengths and limitations of Saccharomyces cerevisiae as a model organism. The method relies on the functional classification of proteins into different biological pathways and processes and on full proteome comparisons between the putative model organism and other organisms for which we would like to extrapolate results. Here we compare S. cerevisiae to 704 other organisms from various phyla. For each organism, our results identify the pathways and processes for which S. cerevisiae is predicted to be a good model to extrapolate from. We find that animals in general and Homo sapiens in particular are some of the non-fungal organisms for which S. cerevisiae is likely to be a good model in which to study a significant fraction of common biological processes. We validate our approach by correctly predicting which organisms are phenotypically more distant from S. cerevisiae with respect to several different biological processes. Conclusions/Significance: The method we propose could be used to choose appropriate substitute model organisms for the study of biological processes in other species that are harder to study. For example, one could identify appropriate models to study either pathologies in humans or specific biological processes in species with a long development time, such as plants.
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The effect of caponisation on carcass composition by parts and tissues was examined. Twenty-eight castrated and twenty male Penedesenca Negra chicks reared under free-range conditions were slaughtered at 28 weeks of age. The birds were castrated at 4 or 8 weeks. The left sides of the carcasses were quartered (wing, breast, thigh and drumstick), and the parts dissected into the tissue components (skin, subcutaneous fat, intermuscular fat, muscle, bone and tendons). Capons showed more abdominal, intermuscular and subcutaneous fat than the cocks, both at the same slaughter age and at the same weight. The breast and thigh were heavier in the capons than in the cocks. However, the whole muscle mass in the breast was increased by caponisation. This favourable effect was achieved at the expense of decreasing the carcass yield. The age of castration up to 8 weeks did not affect the carcass composition of the parts and tissues.
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A clorose variegada dos citros (CVC) é uma doença grave, causada por Xylella fastidiosa. As medidas usuais de controle mostram-se pouco eficientes ou práticas e com alto custo. Dessa forma, o uso de variedades resistentes e/ou tolerantes desponta como a alternativa mais eficiente, razão pela qual se julgou oportuna a realização deste trabalho. O presente estudo teve como objetivo avaliar o comportamento de variedades e clones de laranjas introduzidas em relação a X. fastidiosa. Foram estudados 59 variedades e clones de laranjas doces e 2 de laranjas azedas introduzidos da França, Itália e Portugal. O delineamento experimental foi o de blocos casualizados (DBC), com 62 tratamentos e 4 repetições, incluindo a variedade 'Pêra', como padrão. Cada parcela continha duas plantas, sendo uma inoculada e a outra sem inoculação. Para a inoculação do patógeno, foi empregado o método de encostia, utilizando-se de mudas infectadas. Para a avaliação da incidência da doença, utilizou-se de dados qualitativos, positivos ou negativos, enquanto para severidade empregou-se escala de notas, que foi estabelecida baseando-se nos sintomas de CVC, confirmados através dos testes de PCR. As variedades de laranjas azedas Beja e Sr. Pinto e as laranjas doces Navelina ISA 315, Navelina SRA 332 e Newhall Navel SRA 343 não apresentaram sintomas em folhas até 27 meses após a inoculação.
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Fundamento: El descenso de las tasas de mortalidad por cáncer de mama (CM) se ha atribuido a la implantación de programas de cribado y a avances terapéuticos. El objetivo de este trabajo es comparar la evolución de su mortalidad en las regiones sanitarias de Cataluña en el periodo 1993-2007. Paralelamente, se ha analizado la diseminación de la mamografía periódica en las regiones sanitarias. Métodos: Se analizaron los datos del registro de mortalidad y encuestas de salud. Se utilizaron regresiones de Poisson y «joinpoint» para comparar las tasas de mortalidad por CM y analizar su evolución temporal. Se utilizaron modelos de efectos mixtos para comparar el nivel y la evolución de la mortalidad por regiones. Resultados. La tasa de mortalidad por CM descendió un 3% anual en Cataluña. Entre 1993 y 2007, la tasa estandarizada varió de 34,8 a 23,3 por 100.000 mujeres. Barcelona ciutat presentó unas tasas de mortalidad más elevadas que las regiones Centre (ratio de tasas (RT)=0,87), Costa de Ponent (RT=0,89), Tarragona (RT=0,9) y Lleida (RT=0,915), pero estas diferencias tendieron a desaparecer. No se observaron cambios de tendencia en la evolución de la mortalidad de las regiones, excepto en la región Centre. Durante los años 1990 Barcelona ciutat presentó unos porcentajes de utilización de mamografía periódica del 36,1% de las mujeres de 40-74 años, en la encuesta de 1994, la región Centre (23,7%) y Costa de Ponent (25,2%). Conclusiones: La progresiva utilización de mamografía periódica y la disminución de la mortalidad por CM fueron similares en las regiones sanitarias de Cataluña.
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Este trabalho teve como objetivos verificar se Phyllocnistis citrella ataca plantas de crescimento espontâneo, presentes em pomar de citros orgânicos, identificar nestas plantas outros lepidópteros minadores e seus parasitóides, e verificar se estes parasitóides são os mesmos relatados para P. citrella. O trabalho foi conduzido no município de Montenegro-RS, em um pomar orgânico do híbrido 'Murcott' (Citrus sinensis x C. reticulata). Realizaram-se amostragens quinzenais, de maio de 2003 a maio de 2004, coletando-se, em cada ocasião, todas as folhas com minas contidas na área delimitada por um aro de 0,28 m², que era jogado nas linhas e nas entrelinhas de 30 árvores sorteadas. O material coletado foi levado ao laboratório para triagem. Durante o estudo, foram registradas 11 espécies de lepidópteros minadores e 12 espécies de microimenópteros parasitóides. Alguns gêneros identificados neste estudo já haviam sido relatados em várias regiões do mundo com espécies parasitando P. citrella, tais como Chrysocharis, Closterocerus, Sympiesis (Hymenoptera: Eulophidae) e Bracon (Hymenoptera: Braconidae).
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Background: Breast cancer (BC) causes more deaths than any other cancer among women in Catalonia. Early detection has contributed to the observed decline in BC mortality. However, there is debate on the optimal screening strategy. We performed an economic evaluation of 20 screening strategies taking into account the cost over time of screening and subsequent medical costs, including diagnostic confirmation, initial treatment, follow-up and advanced care. Methods: We used a probabilistic model to estimate the effect and costs over time of each scenario. The effect was measured as years of life (YL), quality-adjusted life years (QALY), and lives extended (LE). Costs of screening and treatment were obtained from the Early Detection Program and hospital databases of the IMAS-Hospital del Mar in Barcelona. The incremental cost-effectiveness ratio (ICER) was used to compare the relative costs and outcomes of different scenarios. Results: Strategies that start at ages 40 or 45 and end at 69 predominate when the effect is measured as YL or QALYs. Biennial strategies 50-69, 45-69 or annual 45-69, 40-69 and 40-74 were selected as cost-effective for both effect measures (YL or QALYs). The ICER increases considerably when moving from biennial to annual scenarios. Moving from no screening to biennial 50-69 years represented an ICER of 4,469€ per QALY. Conclusions: A reduced number of screening strategies have been selected for consideration by researchers, decision makers and policy planners. Mathematical models are useful to assess the impact and costs of BC screening in a specific geographical area.
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O gênero Fusarium é responsável por doenças em diversas plantas economicamente importantes. Entre estas doenças, destaca-se a malformação da mangueira, causada pelo fungo Fusarium subglutinans. O objetivo deste trabalho foi desenvolver oligonucleotídeos iniciadores para reação em cadeia da polimerase (PCR), específicos para o fungo F. subglutinans da mangueira. A amplificação de DNA de oito Fusarium spp. de diferentes hospedeiros, usando o oligonucleotídeo randômico UBC-41 (TTAACCGGGG), produziu um fragmento de aproximadamente 1.300 pb somente para o fungo da mangueira. Tendo em vista que padrões de bandeamento por RAPD não são considerados confiáveis devido à baixa reprodutibilidade dos resultados, o fragmento diferencial foi eluído do gel de agarose, purificado, clonado e seqüenciado. As seqüências nucleotídicas foram utilizadas para identificar e sintetizar quatro pares de oligonucleotídeos específicos, denominados Fs 5, Fs 13, Fs 14 e Fs 15. DNAs de Fusarium spp. de outros hospedeiros (alho, amendoim, cana-de-açúcar, ciclâmen, ervilha, melão e trigo), da planta de mangueira cv. Tommy Atkins sadia e de outros cinco isolados de F. subglutinans de mangueira sintomática, foram submetidos à amplificação com os pares de oligonucleotídeos. Fragmentos amplificados foram visualizados somente para F. subglutinans de mangueira, demonstrando assim a especificidade dos oligonucleotídeos SCAR desenhados.
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The first phytopathogenic bacterium with its DNA entirely sequenced is being detected and isolated from different host plants in several geographic regions. Although it causes diseases in cultures of economic importance, such as citrus, coffee, and grapevine little is known about the genetic relationships among different strains. Actually, all strains are grouped as a single species, Xylella fastidiosa, despite colonizing different hosts, developing symptoms, and different physiological and microbiological observed conditions. The existence of genetic diversity among X. fastidiosa strains was detected by different methodological techniques, since cultural to molecular methods. However, little is know about the phylogenetic relationships developed by Brazilian strains obtained from coffee and citrus plants. In order to evaluate it, fAFLP markers were used to verify genetic diversity and phylogenetic relationships developed by Brazilian and strange strains. fAFLP is an efficient technique, with high reproducibility that is currently used for bacterial typing and classification. The obtained results showed that Brazilian strains present genetic diversity and that the strains from this study were grouped distinctly according host and geographical origin like citrus-coffee, temecula-grapevine-mulberry and plum-elm.
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Signal transduction systems mediate the response and adaptation of organisms to environmental changes. In prokaryotes, this signal transduction is often done through Two Component Systems (TCS). These TCS are phosphotransfer protein cascades, and in their prototypical form they are composed by a kinase that senses the environmental signals (SK) and by a response regulator (RR) that regulates the cellular response. This basic motif can be modified by the addition of a third protein that interacts either with the SK or the RR in a way that could change the dynamic response of the TCS module. In this work we aim at understanding the effect of such an additional protein (which we call ‘‘third component’’) on the functional properties of a prototypical TCS. To do so we build mathematical models of TCS with alternative designs for their interaction with that third component. These mathematical models are analyzed in order to identify the differences in dynamic behavior inherent to each design, with respect to functionally relevant properties such as sensitivity to changes in either the parameter values or the molecular concentrations, temporal responsiveness, possibility of multiple steady states, or stochastic fluctuations in the system. The differences are then correlated to the physiological requirements that impinge on the functioning of the TCS. This analysis sheds light on both, the dynamic behavior of synthetically designed TCS, and the conditions under which natural selection might favor each of the designs. We find that a third component that modulates SK activity increases the parameter space where a bistable response of the TCS module to signals is possible, if SK is monofunctional, but decreases it when the SK is bifunctional. The presence of a third component that modulates RR activity decreases the parameter space where a bistable response of the TCS module to signals is possible.
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Background: Reductions in breast cancer (BC) mortality in Western countries have been attributed to the use of screening mammography and adjuvant treatments. The goal of this work was to analyze the contributions of both interventions to the decrease in BC mortality between 1975 and 2008 in Catalonia. Methodology/Principal Findings: A stochastic model was used to quantify the contribution of each intervention. Age standardized BC mortality rates for calendar years 1975-2008 were estimated in four hypothetical scenarios: 1) Only screening, 2) Only adjuvant treatment, 3) Both interventions, and 4) No intervention. For the 30-69 age group, observed Catalan BC mortality rates per 100,000 women-year rose from 29.4 in 1975 to 38.3 in 1993, and afterwards continuously decreased to 23.2 in 2008. If neither of the two interventions had been used, in 2008 the estimated BC mortality would have been 43.5, which, compared to the observed BC mortality rate, indicates a 46.7% reduction. In 2008 the reduction attributable to screening was 20.4%, to adjuvant treatments was 15.8% and to both interventions 34.1%. Conclusions/Significance: Screening and adjuvant treatments similarly contributed to reducing BC mortality in Catalonia. Mathematical models have been useful to assess the impact of interventions addressed to reduce BC mortality that occurred over nearly the same periods.
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La evaluación de la sostenibilidad en modelos de producción porcina en Cataluña (España), mediante el análisis multicriterio, se estructura en dos partes. Una primera de establecimiento del marco de análisis donde, de forma participativa, se fijan los criterios de evaluación, sus indicadores y las escalas de evaluación. En la segunda se implementa la metología expuesta para evaluar la sostenibilidad de tres modelos productivos y detectar posibles conflictos entre los diferentes grupos de interés. Los resultados obtenidos demuestran que desde el punto de vista de la sostenbilidad, en base a los criterios considerados y bajo distintas opciones de robustez, el modelo productivo más sostenible es el ecológico, seguido del familiar y, en último puesto, el del modelo denominado de integración. En cuanto a la formación de coaliciones se observa que hay un importante grupo de actores que apuestan, en primer lugar, por el modelo de integración. Los anteriores resultados avalan la necesidad de potenciar modelos intermedios entre el ecológico y el de integración. Una opción conciliadora, entre las existentes, podría ser el tipo familiar, aplicando algunas mejoras en el manejo si se quieren satisfacer plenamente los requerimientos de sostenibilidad.
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Um projeto de pesquisa visando à utilização de clones de umezeiro (Prunus mume Sieb. et Zucc.) como porta-enxertos para pessegueiro [Prunus persica (L.) Batsch] está sendo conduzido na FCAV/UNESP, Câmpus de Jaboticabal-SP, com promissoras perspectivas de sucesso. Três genótipos de umezeiro foram selecionados de acordo com características agronômicas desejáveis para esta finalidade. A distinção dos três genótipos entre si, baseada exclusivamente em características morfológicas, apresenta limitações. Dessa forma, o objetivo do presente trabalho foi identificar marcadores RAPD capazes de diferenciar e caracterizar os Clones 05, 15 e a cv. Rigitano (Clone 10) de umezeiro, utilizando-se das cultivares Aurora-1 e Okinawa de pessegueiro como outgroup. Dos 220 primers testados, foram selecionados 42, que amplificaram todos os cinco genótipos. Verificou-se que os marcadores RAPD permitiram a distinção entre o Clone 05, o Clone 15 e a cv. Rigitano de umezeiro, demonstrando a existência de variabilidade genética entre os mesmos. Dentre os três genótipos de umezeiro estudados, constatou-se que a similaridade genética é maior entre o Clone 05 e o Clone 15.