121 research outputs found

    Parque Estadual da Ilha Grande ameaças ambientais e diretrizes para conservação

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    O Parque Estadual da Ilha Grande é somente uma parte (5.594 hectares) de toda a ilha (19.300 hectares) localizada na costa sul do Estado do Rio de Janeiro, entre as cidades de Mangaratiba e Angra dos Reis. Aproximadamente a metade da área do Parque (47%) é coberta por floresta densa, ombrófila, de Mata Atlântica. A mata secundária, em processo de regeneração por sucessão ecológica, está perto da maturidade (43%) e o restante (10%) é composto por áreas antropizadas (1%), afloramentos rochosos com vegetação herbácea (7%), restingas, manguezais e praias (2%). A fauna está bem representada, mas já mostra sinais de degradação com a presença de espécies introduzidas. A análise conduzida sobre o grau de ameaças mostrou que a floresta ombrófila densa está relativamente bem conservada, enquanto a mata secundária, as restingas e mangues e a vegetação herbácea dos terrenos rochosos (e suas respectivas faunas) estão categorizadas como vulneráveis. A área onde há ocupação humana é categorizada como ameaçada. Contraditoriamente, a maior ameaça à biodiversidade local em suas unidades de paisagens é o turismo. Uma vez que a costa onde se localiza a Ilha Grande tem alto valor cênico (conhecida como costa verde pelo constraste entre o mar e o verde da Mata Atlântica que cobre a Serra do Mar), o turismo tem alto potencial para se tornar o meio de atingir a sustentabilidade econômica para conservação. No entanto, por causa do turismo desorganizado e sem controle hoje em prática, com visitantes em número superior à capacidade de suporte na alta estação, a proliferação de hotéis, pousadas e acampamentos e o conseqüente esgoto a céu aberto, depósito de lixo e outras atividades prejudiciais à biodiversidade são as principais ameaças. _______________________________________________________________________________ ABSTRACTThe State Park of Ilha Grande is only a part (5,594 hectares) of the entire island (19,300 hectares) which is located off the south coast of Rio de Janeiro state, between the cities of Mangaratiba and Angra dos Reis. Approximately half of the Park area (47%) is covered by dense Atlantic forest. The secondary forest growth is in a process of ecological succession close to attaining maturity (43%) and the remaining part (10%) is composed of human-altered areas (1%), rocky outcrops with herbaceous vegetation (7%), mangroves and beaches (2%). The fauna is well represented but already shows signs of degradation with introduced species. The analysis of the degree of threat has shown that the dense forest habitat has a relatively stable status of conservation while the secondary forest, the mangrove and the herbaceous vegetation on rocky outcrops (and their fauna) are categorized as vulnerable. The area altered by human occupation is considered threatened. Since the coastal area where Ilha Grande is located is well known for its beautiful scenery (known as the green coast, because of the contrast between the ocean and the Atlantic forest covering the Serra do Mar mountain chain). There is a strong possibility for tourism to become the means in which to achieve economic sustainability for conservation. Contradictorily, tourism is also the major threat to local biodiversity and its landscape units. Because tourism is not organized and controlled, during high season the numbers grow above local capacity, giving rise to a proliferation of hotels, guesthouses and camping grounds. The resulting untreated open sewage, random garbage disposal and other harmful activities form the major threats to biodiversity

    Venezuelan Equine Encephalitis Virus in Iquitos, Peru: Urban Transmission of a Sylvatic Strain

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    Enzootic strains of Venezuelan equine encephalitis virus (VEEV) have been isolated from febrile patients in the Peruvian Amazon Basin at low but consistent levels since the early 1990s. Through a clinic-based febrile surveillance program, we detected an outbreak of VEEV infections in Iquitos, Peru, in the first half of 2006. The majority of these patients resided within urban areas of Iquitos, with no report of recent travel outside the city. To characterize the risk factors for VEEV infection within the city, an antibody prevalence study was carried out in a geographically stratified sample of urban areas of Iquitos. Additionally, entomological surveys were conducted to determine if previously incriminated vectors of enzootic VEEV were present within the city. We found that greater than 23% of Iquitos residents carried neutralizing antibodies against VEEV, with significant associations between increased antibody prevalence and age, occupation, mosquito net use, and overnight travel. Furthermore, potential vector mosquitoes were widely distributed across the city. Our results suggest that while VEEV infection is more common in rural areas, transmission also occurs within urban areas of Iquitos, and that further studies are warranted to identify the precise vectors and reservoirs involved in urban VEEV transmission

    Both SEPT2 and MLL are down-regulated in MLL-SEPT2 therapy-related myeloid neoplasia

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    <p>Abstract</p> <p>Background</p> <p>A relevant role of septins in leukemogenesis has been uncovered by their involvement as fusion partners in <it>MLL</it>-related leukemia. Recently, we have established the <it>MLL-SEPT2 </it>gene fusion as the molecular abnormality subjacent to the translocation t(2;11)(q37;q23) in therapy-related acute myeloid leukemia. In this work we quantified <it>MLL </it>and <it>SEPT2 </it>gene expression in 58 acute myeloid leukemia patients selected to represent the major AML genetic subgroups, as well as in all three cases of <it>MLL-SEPT2</it>-associated myeloid neoplasms so far described in the literature.</p> <p>Methods</p> <p>Cytogenetics, fluorescence in situ hybridization (FISH) and molecular studies (RT-PCR, qRT-PCR and qMSP) were used to characterize 58 acute myeloid leukemia patients (AML) at diagnosis selected to represent the major AML genetic subgroups: <it>CBFB-MYH11 </it>(n = 13), <it>PML-RARA </it>(n = 12); <it>RUNX1-RUNX1T1 </it>(n = 12), normal karyotype (n = 11), and <it>MLL </it>gene fusions other than <it>MLL-SEPT2 </it>(n = 10). We also studied all three <it>MLL-SEPT2 </it>myeloid neoplasia cases reported in the literature, namely two AML patients and a t-MDS patient.</p> <p>Results</p> <p>When compared with normal controls, we found a 12.8-fold reduction of wild-type <it>SEPT2 </it>and <it>MLL-SEPT2 </it>combined expression in cases with the <it>MLL-SEPT2 </it>gene fusion (p = 0.007), which is accompanied by a 12.4-fold down-regulation of wild-type <it>MLL </it>and <it>MLL-SEPT2 </it>combined expression (p = 0.028). The down-regulation of <it>SEPT2 </it>in <it>MLL-SEPT2 </it>myeloid neoplasias was statistically significant when compared with all other leukemia genetic subgroups (including those with other <it>MLL </it>gene fusions). In addition, <it>MLL </it>expression was also down-regulated in the group of <it>MLL </it>fusions other than <it>MLL-SEPT2</it>, when compared with the normal control group (p = 0.023)</p> <p>Conclusion</p> <p>We found a significant down-regulation of both <it>SEPT2 </it>and <it>MLL </it>in <it>MLL-SEPT2 </it>myeloid neoplasias. In addition, we also found that <it>MLL </it>is under-expressed in AML patients with <it>MLL </it>fusions other than <it>MLL-SEPT2</it>.</p

    Riparian Research and Management: Past, Present, Future: Volume 1

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    Fifty years ago, riparian habitats were not recognized for their extensive and critical contributions to wildlife and the ecosystem function of watersheds. This changed as riparian values were identified and documented, and the science of riparian ecology developed steadily. Papers in this volume range from the more mesic northwestern United States to the arid Southwest and Mexico. More than two dozen authors—most with decades of experience—review the origins of riparian science in the western United States, document what is currently known about riparian ecosystems, and project future needs. Topics are widespread and include: interactions with fire, climate change, and declining water; impacts from exotic species; unintended consequences of biological control; the role of small mammals; watershed response to beavers; watershed and riparian changes; changes below large dams; water birds of the Colorado River Delta; and terrestrial vertebrates of mesquite bosques. Appendices and references chronicle the field’s literature, authors, “riparian pioneers,” and conferences

    Cytogenic analysis of cell lines derived from metastases of a mammary carcinoma in a dog

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    Three cell lines derived from two metastases of a mammary carcinoma in a femal dog were analyzed cytogenetically. All three cell lines showed a modal chromosome number of 76, with ranges of 74-77, 72-78, and 73-78. A biarmed chromosome in addition to the X chromosomes was observed in all cells of one cell line, and in a part of the cells of the other two cell lines. Results of banding analyses indicated that this chromosome was identical in the three cell lines, and can thus be considered a clonal marker. Additional biarmed chromosomes have not been reported previously from mammary tumor cells, although their presence is rather common in other canine neoplasms

    Localización y actividad de los genes RNA ribosómico 18s+28s en el cerdo, el Babirusa y el Pécari de hocico blanco

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    En el presente estudio, la hibridación fluorescente in situ ha sido empleada para mapear los clusters - regiones organizadoras del nucleolo o NORs- de genes RNA ribosómico 18S+28S en babirusa, Babyrousa babyrussa (familia Suidae) y el pécari de hocico blanco, Tayassu pecar¡ (familia Dicotylidae). Además, se empleó la tinción selectiva con plata para identificar los genes rRNA que transcriben activamente (Ag-NORs). Los resultados son comparados con los obtenidos previamente para el cerdo doméstico (Sus scrofa) (Bosma et al., 1991; Mellink et al., 1992 y 1994). Los cromosomas metafásicos fueron preparados a partir de linfocitos sanguíneos de un babirusa macho y de un pécari macho siguiendo los procedimientos estándar. Los cromosomas fueron GTG bandeados y fotografiados antes de la hibridación con una sonda rDNA 18S+28S humana biotinilada. La tinción con plata de las NORs fue realizada según la descripción de Mellink et al. (1992), Los números de Ag-NORs fueron determinados en, al menos, 30 células. La numeración de los cromosomas de babirusa se realiza de acuerdo con Bosma y de Haan (1981) y la numeración de los cromosomas de pécari se basa en la de Hufty et al. (1973). En el cerdo, los genes rRNA 18S+28S, se localizan en las constricciones secundarias de los cromosomas 8,10 y 16y las Ag-NORs están presentes en los cromosomas 8 y 10. Las NORs de los cromosomas 8 varían en la propiedad de tinción con plata, mientras que las NORs de ambos homólogos del par 10, son consistentemente Ag-positivas. En el babirusa, hemos mapeado los genes rRNA 18S+28S en los cromosomas 6,8 y 10. Los últimos cromosomas corresponden a loscromosomas 8 y 10 del cerdo doméstico, y mostraron respuestas a la tinción con plata similares a las observadas en el cerdo. Los cromosomas 6 fueron Ag-negativos. En el pécari, hemos localizado los genes rRNA 18S+28S en los lugares de las constricciones secundarias de los cromosomas 4 y 8. La tinción con plata, indica que los genes en esos cuatro dusters son transcripcionalmente activos. Así, en esas tres especies, se ha encontrado que, un máximo de cuatro clusters de genes rRNA, contribuye ala producción de rRNA, aun si hay más clusters presentes
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