994 resultados para Coastal Protection


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The present study aimed to experimentally evaluate the protection role of glycerin preserved bovine peritoneum (BP) against intestinal adhesions to a vascular graft. Experiments were performed on 24 adult rabbits, randomly dived into two groups. All animals were submitted to a vascular graft over the infra-renal aorta and vena cava. Group I (12 animals) was submitted to a BP patch on the retroperitoneal opening, between the vascular prosthetic graft and the intestinal loops. Group II (12 animals) had the retroperitoneal opening sutured. After 7, 14, 28 and 60 days, 3 animals of each group were randomly killed and the retro peritoneum, with or without the BP patch, was removed for histological analysis. The histological analysis showed that the BP stimulated a moderate to intense inflammatory reaction at the beginning of the experiments and on the 60-day evaluation, the inflammatory reaction was mild, limited to the BP border with its histological structure preserved. In conclusion, the BP is a safe and cheap interposition material to be used between vascular grafts and intestinal loops, presenting a protection role against adhesions between them.

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Multiple sclerosis (MS) is a chronic autoimmune demyelinating disease of the central nervous system that causes neurological disorders in young adults. Previous studies in various populations highlighted an association between the HLA-DRB1*1.5 allele and MS. This study investigated the association between HLA-DRB1*15 and other HLA-DRB1 alleles and MS in a Brazilian Caucasian population sample from Londrina, Southern Brazil. HLA-DRB1 alleles were analyzed by polymerase chain reaction with specific sequence oligonucleotide primers in 119 MS patients and in 305 healthy blood donors as a control. Among the MS patients, 89 (75.0%) presented with relapsing remitting MS, 24 (20.0%) with secondary progressive MS and 6 (5.0%) with primary progressive MS. The frequency of the HLA-DRB1*15 allele observed in the MS Brazilian patients was similar to findings reported in previous studies carried out in populations worldwide. However, the results showed a higher frequency of the HLA-DRB1*15 allele in the MS patients compared to the controls, with a relative frequency of 0.1050 (10.50%) and 0.0443 (4.4%), respectively (OR=2.53; 95% CI 1.43-4.46; p=0.0009). A protector allele was also detected. The frequency of the HLA-DRB1*11 allele was reduced in the MS patients compared to the controls, with a relative frequency of 0.1345 (13.4%) and 0.1869 (18.7%), respectively (OR=0.67; 95% CI 0.44-1.03; p=0.0692). The results demonstrated that the HLA-DRB1*15 allele in heterozygosity is positively associated with MS (p=0.0079), and may be considered a genetic marker of susceptibility to the disease. A negative association between the HLA-DRB1*11 allele in homozygosity and MS was also verified (p=0.0418); this allele may be considered a genetic marker of resistance to MS in the Brazilian population.

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P>The aim of this study was to evaluate the frequency of TNFa-e microsatellites and the promoter region (TNF-308 and TNF-238) in HIV/AIDS-infected patients presenting or not lipodystrophy syndrome (LS). The design is the genetic case-control association study. Microsatellite and the TNF promoter region polymorphisms were amplified by PCR and submitted to polyacrylamide gel electrophoresis. The genotypes and allele frequencies for 67 HIV-positive patients with lipodystrophy were compared with 50 HIV-positive patients with no evidence of lipodystrophy and with 131 healthy HIV-negative individuals. The presence of the TNFa5 allele could provide HIV/AIDS patients with protection against developing LS. The presence of TNF-308G allele, as well as of its homozygote TNF-308GG, were associated with susceptibility to developing LS. In addition, the presence of the haplotype TNFe3-d3-238G-308A-c1-a5-b7 suggests protection against developing that syndrome. This study highlights that polymorphic sites spanning the region nearby the TNF locus are associated with LS development in HIV/AIDS patients.

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This book chapter represents a synthesis of the work which started in my PhD and which has been the conceptual basis for all of my research since 1993. The chapter presents a method for scientists and managers to use for selecting the type of remotely sensed data to use to meet their information needs associated with a mapping, monitoring or modelling application. The work draws on results from several of my ARC projects, CRC Rainforest and Coastal projects and theses of P.Scarth , K.Joyce and C.Roelfsema.

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It is well accepted that the Americas were the last continents reached by modern humans, most likely through Beringia. However, the precise time and mode of the colonization of the New World remain hotly disputed issues. Native American populations exhibit almost exclusively five mitochondrial DNA (mtDNA) haplogroups (A-D and X). Haplogroups A-D are also frequent in Asia, suggesting a northeastern Asian origin of these lineages. However, the differential pattern of distribution and frequency of haplogroup X led some to suggest that it may represent an independent migration to the Americas. Here we show, by using 86 complete mitochondrial genomes, that all Native American haplogroups, including haplogroup X, were part of a single founding population, thereby refuting multiple-migration models. A detailed demographic history of the mtDNA sequences estimated with a Bayesian coalescent method indicates a complex model for the peopling of the Americas, in which the initial differentiation from Asian populations ended with a moderate bottleneck in Beringia during the last glacial maximum (LGM), around similar to 23,000 to similar to 19,000 years ago. Toward the end of the LGM, a strong population expansion started similar to 18,000 and finished similar to 15,000 years ago. These results support a pre-Clovis occupation of the New World, suggesting a rapid settlement of the continent along a Pacific coastal route.

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Aminoglycoside antibiotics cause considerable toxicity to the inner ear. A progressive hearing loss at high frequencies resulted from the loss of hair cells in the base of the cochlea and a constant preoccupation with finding a treatment that protects against their toxic effects. A self-protection phenomenon to high ototoxic doses of gentamicin is proposed in this paper. Thirty-eight adult guinea pigs with normal hearing were tested using Preyer`s reflex and the distortion product otoacoustic emission (DPOAE) test, and their cochleae were analyzed by scanning electron microscopy. To the four groups investigated, group I (control) and group II (low dose, 10 mg/kg/day for 30 days) showed a normal DPOEA and normal outer hair cells; group III (high dose, 160 mg/kg/day for 10 days) showed the absence of DPOEA and damage to the outer hair cells; and group IV (low dose, 10 mg/kg/day for 30 days followed by a high dose of 160 mg/kg/day for 10 days) showed a normal DPOEA and normal outer hair cells. These results demonstrate that there was a considerable self-protection phenomenon by gentamicin.

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Coastal wetlands are dynamic and include the freshwater-intertidal interface. In many parts of the world such wetlands are under pressure from increasing human populations and from predicted sea-level rise. Their complexity and the limited knowledge of processes operating in these systems combine to make them a management challenge.Adaptive management is advocated for complex ecosystem management (Hackney 2000; Meretsky et al. 2000; Thom 2000;National Research Council 2003).Adaptive management identifies management aims,makes an inventory/environmental assessment,plans management actions, implements these, assesses outcomes, and provides feedback to iterate the process (Holling 1978;Walters and Holling 1990). This allows for a dynamic management system that is responsive to change. In the area of wetland management recent adaptive approaches are exemplified by Natuhara et al. (2004) for wild bird management, Bunch and Dudycha (2004) for a river system, Thom (2000) for restoration, and Quinn and Hanna (2003) for seasonal wetlands in California. There are many wetland habitats for which we currently have only rudimentary knowledge (Hackney 2000), emphasizing the need for good information as a prerequisite for effective management. The management framework must also provide a way to incorporate the best available science into management decisions and to use management outcomes as opportunities to improve scientific understanding and provide feedback to the decision system. Figure 9.1 shows a model developed by Anorov (2004) based on the process-response model of Maltby et al. (1994) that forms a framework for the science that underlies an adaptive management system in the wetland context.

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The critically endangered black-faced lion tamarin, Leontopithecus caissara, has a restricted geographical distribution consisting of small mainland and island populations, each with distinct habitats in coastal southeastern Brazil. Necessary conservation management actions require an assessment of whether differences in habitats are reflected in use of space by the species. We studied two tamarin groups on the mainland at Sao Paulo state between August 2005 and March 2007, and compared the results with data from Superagui Island. Three home range estimators were used: minimum convex polygon (MCP), Kernel, and the new technique presented dissolved monthly polygons (DMP). These resulted, respectively, in home ranges of 345, 297, and 282 ha for the 12-month duration of the study. Spatial overlap of mainland groups was extensive, whereas temporal overlap was not, a pattern that indicates resource partitioning is an important strategy to avoid intraspecific competition. L. caissara large home ranges seem to be dynamic, with constant incorporation of new areas and abandonment of others through time. The main difference between mainland and island groups is the amount and variety of sleeping sites. A better understanding of the home range sizes, day range lengths, and territorial behavior of this species will aid in developing better management strategies for its protection. Additionally, the presented DMP protocol is a useful improvement over the MCP method as it results in more realistic home range sizes for wildlife species. Am. J. Primatol. 73: 1114-1126, 2011. (C) 2011 Wiley Periodicals, Inc.

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The purposes of this study were to model a vaccination regimen for Newcastle disease virus (NDV) in pigeons, and to evaluate the susceptibility and behavior of vaccinated birds against a highly pathogenic NDV Brazilian strain. Antibody response was assessed by means of hemagglutination inhibition test (HI), and viral genome excretion by means of RT-PCR. Vaccinal strains (La Sota and Ulster) induced high antibody titers without any adverse effects, both in inoculated and in sentinel birds. A viral strain pathogenic for chickens did not produce clinical signs of the disease in experimentally infected pigeons. Only 4 out of 10 vaccinated pigeons shed NDV genome, and just for two days. Results confirmed the high infectivity of the vaccinal strains used, as all nonvaccinated pigeons showed antibody titers as high as those of vaccinated birds.