28 research outputs found

    Chemotherapy followed by low dose radiotherapy in childhood Hodgkin's disease: retrospective analysis of results and prognostic factors

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    PURPOSE: To report the treatment results and prognostic factors of childhood patients with Hodgkin's disease treated with chemotherapy (CT) followed by low dose radiotherapy (RT). PATIENTS AND METHODS: This retrospective series analyzed 166 patients under 18 years old, treated from January 1985 to December 2003. Median age was 10 years (range 2–18). The male to female ratio was 2,3 : 1. Lymphonode enlargement was the most frequent clinical manifestation (68%), and the time of symptom duration was less than 6 months in 55% of the patients. In histological analysis Nodular Sclerosis was the most prevalent type (48%) followed by Mixed Celularity (34.6%). The staging group according Ann Arbor classification was: I (11.7%), II (36.4%), III (32.1%) and IV (19.8%). The standard treatment consisted of chemotherapy multiple drug combination according the period of treatment protocols vigent: ABVD in 39% (n-65) of the cases, by VEEP in 13 %(n-22), MOPP in 13 %(n-22), OPPA-13 %(n-22) and ABVD/OPPA in 22 %(n-33). Radiotherapy was device to all areas of initial presentation of disease. Dose less or equal than 21 Gy was used in 90.2% of patients with most part of them (90%) by involved field (IFRT) or mantle field. RESULTS: The OS and EFS in 10 years were 89% and 87%. Survival according to clinical stage as 94.7%, 91.3%, 82.3% and 71% for stages I to IV(p = 0,005). The OS was in 91.3% of patients who received RT and in 72.6% of patients who did not (p = 0,003). Multivariate analysis showed presence of B symptoms, no radiotherapy and advanced clinical stage to be associated with a worse prognosis. CONCLUSION: This data demonstrating the importance of RT consolidation with low dose and reduced volume, in all clinical stage of childhood HD, producing satisfactory ten years OS and EFS. As the disease is highly curable, any data of long term follow-up should be presented in order to better direct therapy, and to identify groups of patients who would not benefit from radiation treatment

    Preoperative external beam radiotherapy and reduced dose brachytherapy for carcinoma of the cervix: survival and pathological response

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    PURPOSE: To evaluate the pathologic response of cervical carcinoma to external beam radiotherapy (EBRT) and high dose rate brachytherapy (HDRB) and outcome. MATERIALS AND METHODS: Between 1992 and 2001, 67 patients with cervical carcinoma were submitted to preoperative radiotherapy. Sixty-five patients were stage IIb. Preoperative treatment included 45 Gy EBRT and 12 Gy HDRB. Patients were submitted to surgery after a mean time of 82 days. Lymphadenectomy was performed in 81% of patients. Eleven patients with residual cervix residual disease on pathological specimen were submitted to 2 additional insertions of HDRB. RESULTS: median follow up was 72 months. Five-year cause specific survival was 75%, overall survival 65%, local control 95%. Complete pelvic pathological response was seen in 40%. Surgery performed later than 80 days was associated with pathological response. Pelvic nodal involvement was found in 12%. Complete pelvic pathological response and negative lymphnodes were associated with better outcome (p = .03 and p = .005). Late grade 3 and 4 urinary and intestinal adverse effects were seen in 12 and 2% of patients. CONCLUSION: Time allowed between RT and surgery correlated with pathological response. Pelvic pathological response was associated with improved outcome. Postoperative additional HDRB did not improve therapeutic results. Treatment was well tolerated

    Convergence of soil nitrogen isotopes across global climate gradients

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    Quantifying global patterns of terrestrial nitrogen (N) cycling is central to predicting future patterns of primary productivity, carbon sequestration, nutrient fluxes to aquatic systems, and climate forcing. With limited direct measures of soil N cycling at the global scale, syntheses of the (15)N:(14)N ratio of soil organic matter across climate gradients provide key insights into understanding global patterns of N cycling. In synthesizing data from over 6000 soil samples, we show strong global relationships among soil N isotopes, mean annual temperature (MAT), mean annual precipitation (MAP), and the concentrations of organic carbon and clay in soil. In both hot ecosystems and dry ecosystems, soil organic matter was more enriched in (15)N than in corresponding cold ecosystems or wet ecosystems. Below a MAT of 9.8°C, soil δ(15)N was invariant with MAT. At the global scale, soil organic C concentrations also declined with increasing MAT and decreasing MAP. After standardizing for variation among mineral soils in soil C and clay concentrations, soil δ(15)N showed no consistent trends across global climate and latitudinal gradients. Our analyses could place new constraints on interpretations of patterns of ecosystem N cycling and global budgets of gaseous N loss

    Lessons Learned from the Water Producer Project in the Atlantic Forest, Brazil

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    Forest and landscape restoration (FLR) is a powerful strategy for large-scale tropical forest recovery, and payment for ecosystem services (PES) is used to support FLR programs and projects on privately-owned land. In this article, we discuss the lessons learned from the Water Producer Project, a pioneer, multiple-stakeholder, and PES-supported FLR project in the Atlantic Forest, south-eastern Brazil. The project was implemented in four landscapes located in two municipalities. Altogether, 41 PES contracts with landowners were signed, resulting in various FLR practices being implemented in a total of 342.4 ha (64.2 ha for riparian forest restoration, 90.8 ha for soil conservation, and 187.4 for forest conservation) of land, which represents 39% of the project goal. As of the end of the project, only 50% (USD 49,250) of the available PES funds had been spent. However, funds spent on project planning, implementation, communication, and monitoring were 12 times greater than those spent on PES. Several challenges restricted the progress and monitoring of the project. The main issue was landowner participation and/or engagement. In terms of lessons learned, we highlight that PES schemes are more complex than initially thought, and that sufficient funding does not guarantee the success of FLR projects. It is essential to promote landowner participation and engagement by considering them key players in FLR projects. Finally, acceptance from landowners was higher and implementation was easier for forest conservation practices that required no land-use changes. Thus, we suggest that similar future projects should focus on targeting private properties in marginal agricultural lands with a high probability of natural regeneration. Alternatively, future projects could focus on lands with remnant forest cover of high conservation value

    Assessment of the nursery species pool for restoring landscapes in southeastern Brazil

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    Brazil has committed to fulfilling international restoration goals and to enforcing environmental legislation that will require private landowners to undertake ecological restoration of 21 million hectares of degraded and deforested landscapes. To support a broad range of restoration practices, a well-established supply chain capable of representing regional plant diversity is essential. This study investigated the restoration species pool in native plant nurseries in Sao Paulo state, located in southeastern Brazil, and evaluated their geographic distribution, similarity of their plant stocks, and the proportion of species represented from regional floras. Despite a lack of technical assistance and a significant presence of nonnative species (126 species, average 7.5 species/nursery), we found an impressive native species richness in plant nurseries (561 species, average 86.4 species/nursery) from both the Atlantic Forest and Cerrado domains, representing 38-44% of regional floras. There was a huge bias toward tree and shrub species (96.6%) and an absence or underrepresentation of other growth forms, as well as of savanna specialists, animal-dispersed, and threatened species. The dissimilarity of species observed among the different nurseries surveyed highlights their role in representing regional diversity, which reflects their regional seed collection practices. Effective assistance and training are essential to address issues related to misidentification of species, underrepresentation of most functional plant groups, and the presence of nonnative species, as well as to support the supply chain, which is currently undergoing a market downturn282427434CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP140545/2016-6não tem2013/50718-

    Produção de mudas de espécies arbóreas nativas em viveiro via resgate de plantas jovens

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    A dificuldade na obtenção de mudas com alta diversidade nos viveiros florestais tem levado à perda de diversidades biológica e genética nos projetos de restauração de áreas degradadas. Este estudo apresenta alternativa para minimizar esse problema, utilizando a técnica do resgate de plantas jovens, as quais foram obtidas de dois fragmentos florestais em diferentes estádios de sucessão ecológica (média e inicial), localizados no Município de Carandaí, MG. Indivíduos com até 60 cm de altura foram transplantados para viveiro e avaliados durante seis meses. Foi resgatado um total de 966 indivíduos, pertencentes a 26 famílias, num montante de 70 espécies, com maior porcentagem dessas observada no fragmento com estádio sucessional mais avançado. A taxa média de sobrevivência foi de 79,3%, diferindo estatisticamente entre os fragmentos, altura dos indivíduos e espécies. Indivíduos provenientes do fragmento de estádio inicial, assim como os de altura inferior a 40 cm, caracterizaram-se pela maior taxa de sobrevivência. Verificou-se alta sobrevivência de plantas, tanto de espécies pioneiras quanto de não pioneiras, muitas comumente não encontradas nos viveiros florestais e, por consequência, também ausentes nos projetos de restauração. Portanto, a técnica de resgate de plantas jovens é estratégia complementar viável, de baixo custo, que pode contribuir para o aumento da diversidade nos viveiros florestais e nos projetos de restauração florestal

    Environmental gradients and the evolution of successional habitat specialization: A test case with 14 Neotropical forest sites

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    Successional gradients are ubiquitous in nature, yet few studies have systematically examined the evolutionary origins of taxa that specialize at different successional stages. Here we quantify successional habitat specialization in Neotropical forest trees and evaluate its evolutionary lability along a precipitation gradient. Theoretically, successional habitat specialization should be more evolutionarily conserved in wet forests than in dry forests due to more extreme microenvironmental differentiation between early and late-successional stages in wet forest. We applied a robust multinomial classification model to samples of primary and secondary forest trees from 14 Neotropical lowland forest sites spanning a precipitation gradient from 788 to 4000 mm annual rainfall, identifying species that are old-growth specialists and secondary forest specialists in each site. We constructed phylogenies for the classified taxa at each site and for the entire set of classified taxa and tested whether successional habitat specialization is phylogenetically conserved. We further investigated differences in the functional traits of species specializing in secondary vs. old-growth forest along the precipitation gradient, expecting different trait associations with secondary forest specialists in wet vs. dry forests since water availability is more limiting in dry forests and light availability more limiting in wet forests. Successional habitat specialization is non-randomly distributed in the angiosperm phylogeny, with a tendency towards phylogenetic conservatism overall and a trend towards stronger conservatism in wet forests than in dry forests. However, the specialists come from all the major branches of the angiosperm phylogeny, and very few functional traits showed any consistent relationships with successional habitat specialization in either wet or dry forests. Synthesis. The niche conservatism evident in the habitat specialization of Neotropical trees suggests a role for radiation into different successional habitats in the evolution of species-rich genera, though the diversity of functional traits that lead to success in different successional habitats complicates analyses at the community scale. Examining the distribution of particular lineages with respect to successional gradients may provide more insight into the role of successional habitat specialization in the evolution of species-rich taxa. © 2015 British Ecological Society
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