83 research outputs found

    Impact of seedling removal on regenerating community structure of a seasonal semideciduous forest

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    O transplante de plântulas e indivíduos jovens de florestas naturais tem sido considerado como alternativa à produção de mudas de espécies nativas para a restauração florestal, sem que tenham sido realizados estudos sobre os possíveis impactos dessa prática sobre a comunidade vegetal regenerante. Nesse trabalho foram analisadas diferentes intensidades de retirada de plântulas e indivíduos jovens de até 30 cm, de remanescente de Floresta Estacional Semidecidual, a fim de verificar o quanto essa operação pode comprometer a estabilidade da comunidade regenerante. Foram instaladas 80 parcelas de 2×2 m, distribuídas em dois ambientes (borda e interior da floresta) e em quatro tratamentos de retirada de regenerantes (I,II - 100% de retirada com ou sem revolvimento do solo, III - 50% de retirada sem revolvimento do solo e IV - testemunha sem retirada de regenerantes). Avaliou-se a densidade e a riqueza da regeneração antes da execução dos tratamentos e após seis, 12 e 18 meses. Os resultados foram comparados entre tratamentos para cada período de avaliação e entre períodos de avaliação para cada tratamento. Foram constatadas semelhanças entre borda e interior. Não houve incremento da regeneração com revolvimento do solo. Parcelas submetidas à retirada dos regenerantes recuperaram em parte a densidade; porém apresentaram riqueza menor quando comparadas à testemunha e aos valores iniciais antes da execução dos tratamentos. A remoção das plântulas pode comprometer a regeneração de espécies que ocorrem em baixa densidade, o que sugere que a utilização da regeneração natural como fonte de mudas para a restauração florestal seja voltada para espécies abundantes e com estratégias de regeneração conhecidas e não para a comunidade como um todo.Transplanting seedlings and saplings from natural forests has been considered an alternative to producing saplings of native species for forest restoration purposes, but the possible impact of this procedure on plant community regeneration has not been investigated. This work evaluates the impact of different treatments of shrub and tree-seedling (up to 30 cm) removal from a seasonal semideciduous forest fragment located in southeastern Brazil on the natural regeneration process. Eighty 2×2 m plots were installed in two habitats (forest edge and interior) and submitted to four seedling-removal treatments (I, II - 100% removal with or without soil mixing; III - 50% removal without soil mixing; and IV - control treatment without seedling removal). Regeneration density and richness were evaluated before treatment as well as 6, 12 and 18 months later. The results were compared among treatments for each evaluation period and among periods within treatments. There were similarities between edge and interior. The natural regeneration process did not improve with soil mixing. Plots submitted to seedling removal partially recovered plant density; however, these plots had lower species richness when compared to the control and to the initial values before treatment. Seedling removal has a negative impact on the regeneration process of low-density species, thus the use of natural regeneration as a sapling source for forest restoration purposes should focus only on high-density species with well-known regeneration strategies and not on the community as a whole

    Potential of the seedling community of a forest fragment for tropical forest restoration

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    Devido à baixa disponibilidade de mudas nos viveiros florestais, os projetos de restauração florestal são freqüentemente implantados com um número reduzido de espécies. Avaliou-se o potencial da comunidade de plântulas como fonte de mudas para a restauração florestal. Para tanto, a comunidade de plântulas de um remanescente florestal localizado no Sudeste do Brasil foi avaliada. Indivíduos arbustivos ou arbóreos com até 30 cm foram medidos e identificados em 20 parcelas de 4 × 4 m cada. Ao todo foram amostrados 6.136 indivíduos (17 indivíduos m-2), pertencentes a 119 espécies. A comunidade estudada apresentou heterogeneidade espacial em relação à densidade de indivíduos e a composição de espécies e agregação espacial para as 10 espécies mais abundantes. Várias espécies encontradas em alta densidade na comunidade de plântulas não estão disponíveis nos viveiros florestais regionais e, portanto, não são utilizadas em projetos de restauração. Esse resultado e a presença de um alto número de indivíduos e espécies no fragmento florestal sugerem um alto potencial desses tipos de remanescentes como bancos de plântulas com alta diversidade, disponíveis para uso em projetos de restauração.Forest restoration projects are usually planted with a reduced number of species as compared to standing forests, largely due to the low availability of native species in seedling nurseries. In the present study, the potential of the native seedling community as a source of seedlings for forest restoration is analyzed. To do so, the seedling community from a forest fragment located in the southeast of Brazil was evaluated. Individuals (tree and shrub species) up to 30 cm height were measured and identified in 20 4 × 4 m plots. Altogether, 6,136 individuals (17 individuals m-2) belonging to 119 species were sampled. The seedling community showed a spatial heterogeneity with respect to the density of individuals and composition of species, and also a spatial aggregation for the 10 most abundant species. Several species that occurred in high densities in the seedling community are not presently available in regional forest nurseries and are therefore not used in restoration projects. This result and the high number of individuals and species found in the fragment suggest a great potential of this type of forest remnants as a source of highly diverse seedling banks for use in restoration projects

    Survival in nursery of native species saplings obtained from natural regeneration of forest fragments

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    O objetivo deste trabalho foi avaliar a sobrevivência em viveiro de plântulas retiradas da regeneração natural de remanescente de Floresta Estacional Semidecidual, localizado em Bofete, SP. Indivíduos com até 30 cm de espécies arbustivo-arbóreos foram coletados em parcelas instaladas previamente em remanescente florestal, transplantados para viveiro sob sombrite 50%, e avaliados periodicamente durante nove meses. Ao todo foram transferidos para o viveiro 2.424 indivíduos, pertencentes a 110 espécies. A taxa média de sobrevivência foi de 69%, com variação nos resultados para as diferentes espécies, famílias e classes de altura dos indivíduos. Embora espécies pioneiras tenham apresentado taxa de sobrevivência significativamente maior que não pioneiras, várias espécies não pioneiras apresentaram elevada taxa de sobrevivência. Muitas das espécies sobreviventes não são encontradas nos viveiros florestais do Estado de São Paulo. A produção de mudas por meio da transferência da regeneração natural de áreas naturais é uma estratégia complementar viável, que eleva a riqueza de espécies dos viveiros florestais.Seedling survival was evaluated regarding transplanted saplings obtained from natural regeneration of a Semideciduous Seasonal Forest fragment, located at Bofete, São Paulo State, Brazil. Shrub and trees species seedlings up to 30 cm height were collected from samples sited on a forest remnant, transplanted to a nursery under 50% shade tissue, and evaluated periodically during nine months. A total of 2,424 seedlings, belonging to 110 species were transferred to the nursery. Average survival reached 69%, although this survival rate was quite variable according to the species, families and height classes of the evaluated individuals. In spite of the fact that pioneer species presented higher survival rate, several non-pioneer species also obtained high values of survival. Besides, many of the survivor species are usually not available in forest nurseries of the São Paulo State. The transference of seedlings from natural regeneration of forest fragments to forest nurseries seems to be a complementary and a viable method in order to produce saplings of native species, increasing diversity within nurseries with forest restoration purposes

    Tree flora of the Tibagi river basin (Paraná, Brazil): Celastrales sensu Cronquist

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    A study of the tree species of the order Celastrales sensu Cronquist from the Tibagi river basin, Paraná state, Brazil, is presented, based on herbarium material. This basin is subdivided into three zones, from north to south: lower Tibagi (BT), mid Tibagi (MT) and upper Tibagi (AT), each with different environmental conditions and vegetation types. The order Celastrales is represented in the basin by 15 tree species belonging to three families: Aquifoliaceae, Celastraceae and Icacinaceae. Icacinaceae has only two species, Citronella gongonha and C. paniculata. The former is distinguished by a glabrous ovary and leaves that usually bear thorns. Aquifoliaceae has six species: Ilex brasiliensis, I. brevicuspis, I. chamaedryfolia, I. dumosa, I. paraguariensis and I. theezans. These species are found mainly in AT and MT and are distinguished by leaf size, indument, apices and margins, and by sepal features. Celastrales is represented by seven species and two genera; Plenckia populnea, a Brazilian savannah species found only in MT, and six species of Maytenus (M. evonymoides, M. robusta, M. dasyclada, M. salicifolia, M. ilicifolia and M. aquifolia) distinguished by leaf size and margins, branch shape and number of flowers per inflorescence.Este trabalho estudou, por meio de coleções de herbários, os representantes arbóreos da ordem Celastrales sensu Cronquist, encontrados na bacia do rio Tibagi, estado do Paraná, Brasil. Esta bacia hidrográfica, subdividida em três zonas de norte para sul, baixo Tibagi (BT), médio Tibagi (MT) e alto Tibagi (AT), apresenta diferentes condições ambientais e tipos de vegetação ao longo de sua extensão. A ordem Celastrales está representada na bacia estudada por 15 espécies arbóreas, pertencentes às famílias Aquifoliaceae, Celastraceae e Icacinaceae. Icacinaceae conta com apenas duas espécies, Citronella gongonha e C. paniculata, sendo a primeira distinta pelo ovário glabro e folhas geralmente com espinhos. Aquifoliaceae contém seis espécies: Ilex brasiliensis, I. brevicuspis, I. chamaedryfolia, I. dumosa, I. paraguariensis e I. theezans, que ocorrem preferencialmente no AT e MT e se distinguem pela dimensão, revestimento, ápice e margem da folha e pela morfologia das sépalas. Celastraceae está representada por sete espécies pertencentes a dois gêneros, Plenckia populnea, espécie de cerrado, encontrada apenas no MT e seis espécies de Maytenus (M. aquifolia, M. dasyclada, M. evonymoides, M. ilicifolia, M. robusta e M. salicifolia), com distinção baseada principalmente no tipo de margem e dimensão das folhas, forma do ramo e número de flores por inflorescência.457472Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

    Whole brain radiation therapy in management of brain metastasis: results and prognostic factors

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    PURPOSE: To evaluate the prognostic factors associated with overall survival in patients with brain metastasis treated with whole brain radiotherapy (WBRT) and estimate the potential improvement in survival for patients with brain metastases, stratified by the Radiation Therapy Oncology Group (RTOG) recursive partitioning analysis (RPA) class. PATIENTS AND METHODS: From January 1996 to December 2000, 270 medical records of patients with diagnosis of brain metastasis, who received WBRT in the Hospital do Cancer Sao Paulo A.C. Camargo in the period, were analyzed. The surgery followed by WBRT was used in 15% of patients and 85 % of others patients were submitted at WBRT alone; in this cohort 134 patients (50%) received the fractionation schedule of 30 Gy in 10 fractions. The most common primary tumor type was breast (33%) followed by lung (29%), and solitary brain metastasis was present in 38.1% of patients. The prognostic factors evaluated for overall survival were: gender, age, Karnofsky Performance Status (KPS), number of lesions, localization of lesions, primary tumor site, surgery, chemotherapy, absence extracranial disease, RPA class and radiation doses and fractionation. RESULTS: The OS in 1, 2 and 3 years was 25, 1%, 10, 4% e 4, 3% respectively, and the median survival time was 4.6 months. The median survival time in months according to RPA class after WBRT was: 6.2 class I, 4.2 class II and 3.0 class III (p < 0.0001). In univariate analysis, the significant prognostic factors associated with better survival were: KPS higher than 70 (p < 0.0001), neurosurgery (p < 0.0001) and solitary brain metastasis (p = 0.009). In multivariate analysis, KPS higher than 70 (p < 0.001) and neurosurgery (p = 0.001) maintained positively associated with the survival. CONCLUSION: In this series, the patients with higher perform status, RPA class I, and treated with surgery followed by whole brain radiotherapy had better survival. This data suggest that patients with cancer and a single metastasis to the brain may be treated effectively with surgical resection plus radiotherapy. The different radiotherapy doses and fractionation schedules did not altered survival

    A regeneração natural sob plantações florestais: desertos verdes ou redutos de biodiversidade?

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    Although commercial forest plantations have been termed “green deserts”, several studies from the last two decades have reported the opposite. These studies suggest that forest plantations can catalyze the natural regeneration in their understory and, thus, contribute to biodiversity conservation. In order to obtain a wide and multi-faceted panorama of forest plantations and their potential contribution to biodiversity conservation and forest restoration, previous studies investigating natural regeneration under forest plantations have been reviewed, highlighting those carried out in Brazil. Methods and environmental conditions are quite variable among studies, making generalizations difficult. Nevertheless, results indicate that historical and environmental factors, such as canopy density and light availability, plantation age, forest species, distance from natural forests, silvicultural practices, and previous land use directly or indirectly affect natural regeneration richness, abundance and community structure under forest plantations. The reviewed studies, as a whole, reinforce the idea that commercial forest plantations can act as environments of biodiversity, at least for some life forms, and, in addition, can facilitate the restoration of native forests. Although the Brazilian studies are abundant, they have been restricted to a few regions and biomes and are mostly descriptive studies. Experimental studies focusing on specific factors that affect the natural regeneration dynamic under forest plantations as well as on management techniques in order to combine high production and biodiversity conservation are desirable. Nonetheless, other biomes and regions rather than those already studied, where forest plantation is a common land use, should be considered.Se, por um lado, plantios florestais comerciais têm sido apontados como "desertos verdes", por outro, diversos estudos realizados nas últimas duas décadas demonstram o contrário, sugerindo que tais florestas podem catalisar a regeneração natural em seu sub-bosque e, assim, contribuir para a conservação da biodiversidade. Com a finalidade de obter uma visão ampla e multifacetada sobre as plantações florestais e seu potencial para a conservação e a restauração da diversidade biológica, efetuou-se a compilação dos principais resultados de estudos que tratam da regeneração natural sob plantios florestais, com destaque para os realizados no Brasil. Os resultados compilados são bastante heterogêneos, indicando que fatores históricos e ambientais, como densidade de copas e disponibilidade de luz no sub-bosque, idade do plantio, espécie florestal plantada, distância de remanescentes de vegetação nativa, manejo das florestas plantadas e histórico de utilização da área influenciam direta ou indiretamente a riqueza, a densidade e a estrutura da regeneração natural sob os plantios. No entanto, inevitavelmente, os estudos investigados reforçam a idéia de que plantios florestais comerciais podem funcionar como redutos da biodiversidade, ao menos para alguns grupos de seres vivos, e também como facilitadores da restauração ecológica de florestas nativas. Com relação ao Brasil, conclui-se que, embora abundantes, os estudos já feitos concentram-se em determinadas regiões e biomas e são, em sua maioria, descritivos. É desejável, portanto, a realização de estudos que investiguem experimentalmente os fatores específicos que influenciam a dinâmica da regeneração natural sob os plantios e sistemas de manejo que proporcionem uma combinação ótima de produção e conservação da biodiversidade. É desejável ainda que esses estudos abranjam também outras regiões fitogeográficas do País, onde plantações florestais também são expressivas

    Intensity Modulated Radiotherapy (IMRT) in the postoperative treatment of an adenocarcinoma of the endometrium complicated by a pelvic kidney

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    BACKGROUND: Pelvic Radiotherapy (RT) as a postoperative treatment for endometrial cancer improves local regional control. Brachytherapy also improves vaginal control. Both treatments imply significant side effects that a fine RT technique can help avoiding. Intensity Modulated RT (IMRT) enables the treatment of the target volume while protecting normal tissue. It therefore reduces the incidence and severity of side effects. CASE: We report on a 50 year-old patient with a serous-papiliferous adenocarcinoma of the uterus who was submitted to surgical treatment without lymph node sampling followed by Brachytherapy, and Chemotherapy. The patient had a pelvic kidney, and was therefore treated with IMRT. So far, the patient has been free from relapse and with normal kidney function. CONCLUSION: IMRT is a valid technique to prevent the kidney from radiation damage

    Floristic and structural characterization of forest remnants in Quedas do Iguaçu, Southeastern Paraná

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    O sudoeste paranaense localiza-se na transição entre a Floresta Estacional Semidecidual (FES) e a Floresta Ombrófila Mista (FOM), numa região de grande relevância ecológica, por conter duas importantes formações florestais do sul-sudeste brasileiro. Entretanto, essa mesma região é marcada pela escassez de levantamentos florísticos e de caracterização da vegetação. Nesse trabalho é feita a caracterização florística e estrutural de três áreas de vegetação nativa, localizadas em Quedas do Iguaçu, sudoeste do Paraná, na bacia do rio Iguaçu. Além disso, foi feita a caracterização fitogeográfica das florestas estudadas, com base nos dados coletados e na listagem de espécies amostradas em outras 52 áreas de FES ou FOM do Brasil. Em cada uma das três áreas estudadas, a vegetação arbustivo-arbórea (diâmetro à altura do peito > 5 cm) foi caracterizada por meio da alocação de pontos quadrantes. No total foram encontradas 128 espécies, com variação entre 63 a 78 para cada área. Cada área apresentou distinção quanto à estrutura e às espécies mais abundantes. Além disso, as áreas se distinguem quanto ao grau de influência da FES e da FOM em sua composição florística. Comparativamente, a área de menor altitude, localizada no vale do Rio Iguaçu, apresenta mais elementos de FES em sua composição florística, enquanto as outras duas áreas, localizadas em trechos mais elevados, têm maior influência da FOM, contando inclusive com a ocorrência de Araucaria angustifolia (Bertol.) Kuntze.The Southwestern region of Paraná State is an area of great ecological relevance because it represents an ecotone between two important forest types of the Brazilian south-southeastern region: the Seasonal Semideciduous Forest (SSF) and the Araucaria Forest (AF). Despite its importance, there is a lack of floristic surveys and vegetation studies in this region. In this study, we assessed floristic and structural attributes of the vegetation at three different native forest sites, located in Quedas do Iguaçu, Paraná State. Moreover, we made a phytogeografical characterization of the studied forests, based on the data we collected, and on the list of species surveyed in other 52 studies in SSF and AF of Brazil. Samples were taken using the point-centered-quarter method. All individuals with diameter at breast height > 5 cm were identified to the species level. Together, 128 species were found. Within sites, the number of species varied from 63 to 78. The three areas are distinguished with respect to structure and most abundant species. In addition, the areas differed with respect to the degree of influence of SSF and AF on their floristic composition. Comparatively, the lower altitude area, located in Iguaçu River's valley, has more elements of SSF on its floristic composition, while the other two areas, located in higher altitude areas, are more influenced by AF, with Araucaria angustifolia (Bertol.) Kuntze on their list of species

    High-risk surgical stage 1 endometrial cancer: analysis of treatment outcome

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    PURPOSE: To report the relapse and survival rates associated to treatment for patients with stage IC, grade 2 or grade 3 and IB grade 3 diseases considered high risk patients group for relapse. MATERIALS AND METHODS: From January 1993 to December 2003, 106 patients with endometrial cancer stage I were managed surgically in our institution. Based on data from the medical records, 106 patients with epithelial endometrial cancer met the following inclusion criteria: stage IC grade 2 or 3 and IB grade 3 with or without lymphovascular invasion. Staging was defined according to the FIGO surgical staging system. Postoperative adjuvant radiotherapy consisted of external beam pelvic radiation, vaginal brachytherapy alone or both. The median age was 65 years (range, 32–83 years), lymph node dissection was performed in 45 patients (42.5%) and 14 patients (13.2%) received vaginal brachytherapy only, and 92 (86.8%) received combined vaginal brachytherapy and external beam radiotherapy. The median dose of external beam radiotherapy administered to the pelvis was 4500 cGy (range 4000 – 5040). The median dose to vaginal surface was 2400 cGy (range 2000 – 3000). Predominant pathological stage and histological grade were IC (73.6%) and grade 3 (51.9%). The lymphovascular invasion was present in 33 patients (31.1%) and pathological stage IC grade 2 was most common (48. 1%) combination of risk factors in this group. RESULTS: With a follow up median of 58.3 months (range 12.8 – 154), five year overall survival and event free survival were 78.5% and 72.4%, respectively. Locoregional control in five year was 92.4%. Prognostic factors related with survival in univariate analyses were: lymphadenectomy (p = 0.045), lymphovascular invasion (p = 0.047) and initial failure site (p < 0.0001). In multivariate analyses the initial failure in distant sites (p < 0.0001) was the only factor associated with poor survival. Acute and chronic gastrointestinal and genitourinary toxicity grades 3 were not observed. CONCLUSION: In conclusion, our results showed that the stage IC, grade 2, 3 and IB grade 3 endometrial cancer was associated with significantly increased risk of distant relapse and endometrial carcinoma-related death independently of salvage treatment modality

    Salvage radiotherapy for biochemical relapse after complete PSA response following radical prostatectomy: outcome and prognostic factors for patients who have never received hormonal therapy

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    OBJECTIVES: To evaluate the results of salvage conformal radiation therapy (3DC-EBRT) for patients submitted to radical prostatectomy (RP) who have achieved complete PSA response and who have never been treated with hormonal therapy (HT). To present the results of biochemical control, a period free from hormonal therapy and factors related to its prognosis. MATERIALS AND METHODS: from August 2002 to December 2004, 43 prostate cancer patients submitted to RP presented biochemical failure after achieving a PSA < 0.2 ng/ml. They have never received HT and were submitted to salvage 3DC-EBRT. Median age was 62 years, median preoperative PSA was 8.8 ng/ml, median Gleason Score was 7. Any PSA rise above 0.2 was defined as biochemical failure after surgery. Median 3DC-EBRT dose was 70 Gy, biochemical failure after EBRT was defined as 3 consecutive rises in PSA or a single rise enough to trigger HT. RESULTS: 3-year biochemical non-evidence of disease (BNED) was 71%. PSA doubling time lower than 4 months (p = 0.01) and time from recurrence to salvage EBRT (p = 0.04) were associated with worse chance of biochemical control. Biochemical control of 76% was achieved when RT had been introduced with a PSA lower than 1 ng/ml vs. 48% with a PSA higher than 1 (p = 0.19). Late toxicity was acceptable. CONCLUSION: 70% of biochemical control in 3 years can be achieved with salvage radiotherapy in selected patients. The importance of PSADT was confirmed in this study and radiotherapy should be started as early as possible. Longer follow up is necessary, but it is possible to conclude that a long interval free from hormonal therapy was achieved with low rate of toxicity avoiding or at least delaying several important adverse effects related to hormonal treatment
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