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51.
Leonardo Manir Feitosa Lucas Pereira Martins Leandro Augusto de Souza Junior Rosangela Paula Lessa 《水产资源保护:海洋与淡水生态系统》2020,30(5):882-891
- Updated distribution ranges are crucial for conservation status assessments. Comprehensive analyses combining published literature and available data on historical catches and species distribution models (SDMs) are effective tools that could improve the prediction of more realistic scenarios for some species, especially those with limited information available and facing multiple threats.
- The present study aimed at generating an updated distribution for the smalltail shark Carcharhinus porosus, one of the most threatened and understudied shark species of the western Atlantic Ocean. Estimates of the key areas for this species conservation based on the SDMs, and trends in catch probabilities throughout its distribution range are provided.
- Four algorithms (BIOCLIM, Domain, Mahalanobis, and Maximum Entropy) were used to model the distribution of C. porosus and calculate its habitat suitability based on marine environmental variables. To assess historical catch probability trends, we built a generalized linear model from published and grey literature data. This analysis was used to estimate catch probability as an indication of population trends.
- SDMs suggest that the northern coast of South America (NCSA) harbours the most suitable habitats for C. porosus in the world, which was expected given its historically high catch rate in this region. In addition, there was a continuously declining catch probability trend starting in the 1970s. However, the decline was smaller for the NCSA as compared with the Gulf of Mexico and the eastern South America coast.
- Results indicate that the NCSA should be considered the currently most important area in the world for this species conservation. Furthermore, the lack of data throughout Central and South American marine regions hampers the evaluation of extinction risk throughout its updated distribution. Thus, research in these areas is urgently required for a more comprehensive conservation status assessment.
52.
Leandro Nole Eduardo Arnaud Bertrand Thierry Frdou Alex Souza Lira Rayssa Siqueira Lima Beatrice Padovani Ferreira Frdric Menard Flvia Lucena‐Frdou 《水产资源保护:海洋与淡水生态系统》2020,30(4):761-774
- Tetraodontiformes fishes play a critical role in benthic and demersal communities and are facing threats due to anthropogenic impacts and climate change. However, they are poorly studied worldwide. To improve knowledge on the socio‐ecological significance and conservation of Tetraodontiformes a review of literature addressing the diversity, ecology, use and trade, conservation, and main threats of Tetraodontiformes combined with a comprehensive in situ dataset from two broad‐range multidisciplinary oceanographic surveys performed along the Tropical Brazilian Continental Shelf was undertaken.
- Twenty‐nine species were identified, being primarily found on coral reefs and algal ecosystems. At these habitats, tetraodontids present highly diversified trophic categories and might play an important role by balancing the marine food web
- Coral reef ecosystems, especially those near to the shelf break, seem to be the most important areas of Tetraodontiformes fishes, concentrating the highest values of species richness, relative abundance and the uncommon and Near Threatened species.
- Ninety per cent of species are commonly caught as bycatch, being also used in the ornamental trade (69%) and as food (52%), serving as an important source of income for artisanal local fisheries.
- Tetraodontiformes are threatened by unregulated fisheries, overexploitation, bycatch, and habitat loss due to coral reef degradation and the potential effects of climate change. These factors are more broadly impacting global biodiversity, food security, and other related ecosystem functions upon which humans and many other organisms rely.
- We recommend the following steps that could improve the conservation of Tetraodontiformes along the tropical Brazilian Continental shelf and elsewhere: (i) data collection of the commercial, incidental, ornamental and recreational catches; (ii) improvement of the current legislation directed at the marine ornamental harvesting; (iii) increase efforts focused on the education and conservation awareness in coastal tourism and communities; and, most important, (iv) creation of marine reserves networks in priority areas of conservation, protecting either the species and key habitats for its survival.
53.
Laura de Andrade Moura Ana Carolina Marqui de Almeida Thaisa Francielle Souza Domingos Fredy Ortiz-Ramirez Diana Negr?o Cavalcanti Valéria Laneuville Teixeira André Lopes Fuly 《Marine drugs》2014,12(5):2471-2484
Cardiovascular diseases represent a major cause of disability and death worldwide. Therapeutics are available, but they often have unsatisfactory results and may produce side effects. Alternative treatments based on the use of natural products have been extensively investigated, because of their low toxicity and side effects. Marine organisms are prime candidates for such products, as they are sources of numerous and complex substances with ecological and pharmacological effects. In this work, we investigated, through in vitro experiments, the effects of three diterpenes (pachydictyol A, isopachydictyol A and dichotomanol) from the Brazilian marine alga, Dictyota menstrualis, on platelet aggregation and plasma coagulation. Results showed that dichotomanol inhibited ADP- or collagen-induced aggregation of platelet-rich plasma (PRP), but failed to inhibit washed platelets (WP). In contrast, pachydictyol A and isopachydictyol A failed to inhibit the aggregation of PRP, but inhibited WP aggregation induced by collagen or thrombin. These diterpenes also inhibited coagulation analyzed by the prothrombin time and activated partial thromboplastin time and on commercial fibrinogen. Moreover, diterpenes inhibited the catalytic activity of thrombin. Theoretical studies using the Osiris Property Explorer software showed that diterpenes have low theoretical toxicity profiles and a drug-score similar to commercial anticoagulant drugs. In conclusion, these diterpenes are promising candidates for use in anticoagulant therapy, and this study also highlights the biotechnological potential of oceans and the importance of bioprospecting to develop medicines. 相似文献
54.
Sandro Froehner Daniele Botelho Souza Karina Scurupa Machado Edson Cordova da Rosa 《Water, air, and soil pollution》2010,210(1-4):33-41
The Barigüi River watershed is located in the metropolitan region of Curitiba, Southern Brazil, passing through several neighboring counties. In recent years, due to growth and disorderly occupation along the river, in addition to lack of sanitation, the Barigüi River suffered a very large inflow of untreated domestic wastewater. Current programs to monitor the watershed use traditional physical–chemical parameters. Here, the presence of some molecular tracers found in domestic effluents was investigated, such as caffeine and coprostanol at some selected sites in Barigüi River. Caffeine is highly soluble in water and its presence in water bodies is due to the disposal of untreated sewage. Caffeine is eliminated in the urine (approximately 0.5% to 10% of the consumption). The samples were collected in three campaigns, two in dry weather and another during a week in the rainy season. The results showed that caffeine concentration ranged between zero and 753.5 μg g?1. Higher values were found on rainy days. Caffeine showed a positive correlation between BOD and nitrate; it also showed a positive correlation with coprostanol, a fecal biomarker. Finally, caffeine has been shown to be a good parameter to determine the contamination by domestic wastewater. 相似文献
55.
F. T. Conceição D. S. Sardinha A. D. G. Souza G. R. B. Navarro 《Water, air, and soil pollution》2010,205(1-4):79-91
The chemical dynamics at Meio Stream Basin, São Paulo State, Brazil were evaluated using major elements as natural tracers. The surface water samples from Meio Stream were collected near the mouth of Meio Stream at the confluence with the Mogi-Guaçu River on February 25, 2005, April 20, 2005, and July 8, 2005. Rainwater samples were collected (using a “bulk” collector) for 1 year at one sampling point located about 4 km from downtown Leme city and other possible sources of contamination. The analyses were performed by pH, temperature, dissolved oxygen, electrical conductivity, total solids, sulfate, nitrate, phosphate, alkalinity, chloride, sodium, calcium, potassium, and magnesium. This basin has serious environmental problems in terms of rainwater and surface water quality, which result in the negative annual flux of cations and anions at Meio Stream Basin, with the exception of chlorine. The Meio Stream, downstream from Leme city, receives several elements/compounds through anthropogenic activities, mainly related to the discharge of domestic effluents. Anthropogenic inputs (mining, fossil fuel burning, and agricultural activities) are responsible for the higher concentrations of cations and anions in the rainwater from this basin. 相似文献
56.
A. S. Moore § A. R. Imondi P. L. de Souza C. A. Wood † 《Veterinary and comparative oncology》2003,1(2):86-93
A colloidal dispersion formulation of 9‐aminocamptothecin (9‐AC) was administered intravenously to 10 dogs with previously untreated, spontaneously occurring, multicentric lymphoma. The dogs received a 72‐h infusion of 9‐AC at a rate of 46.5–51.25 µg m?2 h?1 (total dose range 3.35–3.69 mg m?2). This dose range was associated with myelosuppression, consisting principally of neutropenia with a nadir at 7 days following the start of infusion. Neutropenia and thrombocytopenia were the most common toxicoses and are most likely to be dose‐limiting toxicities; low‐grade gastrointestinal signs were rarely seen. Concentrations of 9‐AC lactone, as well as clinical toxicities, compare favourably with those found in humans. Tumour responses were seen in all treated dogs. Response to other chemotherapy, following cessation of 9‐AC treatment, was not obviously compromised even in dogs clinically resistant to 9‐AC. 9‐AC is a novel treatment drug for canine lymphoma, which appears to show great promise. 相似文献
57.
Adjuvant effect of green propolis on humoral immune response of bovines immunized with bovine herpesvirus type 5 总被引:1,自引:0,他引:1
Fischer G Cleff MB Dummer LA Paulino N Paulino AS de Oliveira Vilela C Campos FS Storch T D'Avila Vargas G de Oliveira Hübner S Vidor T 《Veterinary immunology and immunopathology》2007,116(1-2):79-84
Despite recent technological advances in vaccine production, most vaccines depend on the association with adjuvant substances. In this study, propolis, which has been attracting the attention of researchers due to its bioactive properties, was evaluated as an immunological adjuvant. The association of 40mg/dose of an ethanolic extract of green propolis with an inactivated oil vaccine against bovine herpesvirus type 5 (BoHV-5), resulted in a significant increase (P<0.01) in the neutralizing antibody levels, comparing to the bovines that received the same vaccine without propolis. Besides, propolis increased the percentage of animals with high antibody titers (above 32). Phenolic compounds such as artepillin C (3,5-diprenyl-4-hydroxycinnamic acid) and the derivatives of cinnamic acid besides other flavonoid substances were abundant in the propolis extract used, and they could be the main substances with adjuvant action. The effect of the green propolis extract on the humoral immune response can be exploited in the development of new vaccines. 相似文献
58.
Juliano Lino Ferreira José Eustáquio de Souza Carneiro Alexsandro Lara Teixeira Fabiéli Fortunata de Lanes Paulo Roberto Cecon Aluízio Borém 《Euphytica》2007,153(1-2):165-170
This study was conducted in Brazil in order to assess the potential risk posed by gene escape from transgenic into non-transgenic plants and wild populations. A new methodology was applied to evaluate the gene flow between common bean cultivars, by means of a specially delineated experiment in two stages. The first stage consisted of the planting of one cultivar with violet flowers (BB) as pollen source (‘Diamante Negro’), and a receiver (‘Talismã’) with white flowers (bb), at different distances. The source was sown in the center of the area. The pollen receiver cultivar was sown, in concentrical squares around it. At maturity, the rows were sampled at varied distances from the source in the four cardinal directions. In the second stage, the sampled seeds of the previous stage were sown, and the percentage of outcrossing was evaluated during flowering through the presence of violet flowers (Bb). The highest frequency of natural hybrids, 0.136%, occurred at a distance of 0.5 m between the cultivars. The natural outcrossing rate was practically zero beyond a distance of 3.25 m. 相似文献
59.
Luciana Rossini Pinto Maria Lucia Carneiro Vieira Cláudio Lopes de Souza Jr Anete Pereira de Souza 《Euphytica》2003,134(3):277-286
BR-105 and BR-106 are important tropical maize populations, which were submitted to a high-intensity reciprocal recurrent
selection, generating the IG-3 and IG-4synthetics. Using 30-microsatellite loci,we measured and compared the genetic diversity
of these populations and their synthetics. The populations did not differ significantly regarding the amount of genetic diversity.
As a consequence of selection, genetic variability losses, in terms of mean number of alleles per locus,proportion of polymorphic
loci, and gene diversity did occur and were greater in the synthetic IG-3 than IG-4. In the synthetics, the number of loci
in adherence to Hardy-Weinberg proportions was superior to that observed in the populations. The Wright's mean fixation index
was higher than the mean value expected for outcrossing species (5%) indicating as light excess of homozygotic individuals
in both populations. The genetic distances confirmed the favourable effects of one cycle of recurrent selection, as the synthetics
became more isolated in comparison to the original populations.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
60.
Cordenunsi BR De Menezes Wenzel E Genovese MI Colli C De Souza Gonçalves A Lajolo FM 《Journal of agricultural and food chemistry》2004,52(11):3412-3416
The seeds of Parana pine (Araucaria brasiliensis syn. Araucaria angustifolia), named pinh?o, are consumed after cooking and posterior dehulling, or they are used to prepare a flour employed in regional dishes. Native people that live in the South of Brazil usually consume baked pinh?o. As a result of cooking, the white seeds become brown on the surface due to the migration of some tinted compounds present in the seed coat. In this work, the proximate composition, minerals, flavonoids, and glycemic index (GI) of cooked and raw pinh?o seeds were compared. No differences in moisture, lipids, soluble fiber, and total starch after boiling were found. However, the soluble sugars and P, Cu, and Mg contents decreased, probably as a consequence of leaching in the cooking water. Also, the boiling process modified the profile of the phenolic compounds in the seeds. No flavonols were detected in raw pinh?o seeds. The internal seed coat had a quercetin content five times higher than that of the external seed coat; also, quercetin migrated into the seed during cooking. The internal seed coat had a high content of total phenolics, and seeds cooked in normal conditions (with the seed coat) showed a total phenolics content five times higher than that of seeds cooked without the seed coat. Cooking was then extremely favorable to pinh?o seeds bioactive compounds content. The carbohydrate availability was evaluated in a short-term assay in humans by the GI. The GI of pinh?o seeds cooked with the coat (67%) was similar to that of the seeds cooked without a coat (62%) and lower than bread, showing that cooking does not interfere with starch availability. The low glycemic response can be partly due to its high content of resistant starch (9% of the total starch). 相似文献