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41.
Tenório Mda S Oliveira e Sousa L Paix?o Mdos S Alves MF Paulan Sde C Lima FL Jusi MM Tasca KI Machado RZ Starke-Buzetti WA 《Journal of zoo and wildlife medicine》2011,42(4):608-616
Visceral leishmaniasis (VL) is a zoonotic disease with worldwide distribution. The crab-eating fox (Cerdocyon thous) is considered a wild reservoir of many zoonotical diseases, particularly VL. This study reported the presence of Leishmania infantum amastigotes in different organs of one captive C. thous found dead in a zoo. This animal was positive by the indirect fluorescence antibody test and had many clinical signs of VL. Intracellular amastigote forms of L. infantum were seen in neutrophils and macrophages in sample tissues from skin, lymph nodes (popliteal, submandibular, prescapular, and mesenteric), spleen, and liver. The numbers of positive cells and intracellular parasites were higher in macrophages than in neutrophils. In addition, polymerase chain reaction demonstrated extensive distribution of Leishmania DNA in C. thous tissues from multiple organs. The presence of intracellular amastigotes in neutrophils and macrophages as well as DNA of the parasite in tissues, specifically skin demonstrate that this crab-eating fox is an adequate host for L. infantum and reinforce the importance of VL for symptomatic wild canids kept in captivity in endemic areas. 相似文献
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Kerr RM Tombokan X Ghosh S Martini S 《Journal of agricultural and food chemistry》2011,59(6):2689-2695
This research evaluates the effect of sunflower oil wax (SFOw) addition on the crystallization behavior and functional properties of anhydrous milk fat (AMF). Induction times of nucleation, melting behavior, microstructure of crystals, and hardness were evaluated for samples of pure AMF and AMF with 0.1 and 0.25% SFOw. Results from this research show that the addition of waxes induced the onset of crystallization of AMF by inducing its nucleation, as evidenced by decreased induction times of nucleation and the formation of smaller crystals. Crystal growth after tempering was also promoted by waxes, and significantly harder lipid networks were obtained. Results presented in this paper suggest that SFOw can be used as an additive to alter the physiochemical properties of low trans-fatty acid lipids. 相似文献
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Alejandro Cánepa Silvana B. Basack Norma B. Casabé Noemí R. Verrengia Guerrero 《Journal of Soils and Sediments》2013,13(4):775-782
Purpose
The relative sensitivity of two freshwater invertebrate organisms to the organophosphorus insecticide fenitrothion was assessed by measuring cholinesterase (ChE) activity, a well-known biomarker of both exposure and effect to organophosphorus pesticides. The influence of different concentrations of humic acids (HAs) and particulate matter on fenitrothion bioavailability was assessed in the more sensitive species.Materials and methods
The selected invertebrates were the dwelling feeding oligochaete Lumbriculus variegatus and the pulmonate gastropod Biomphalaria glabrata. Acute 48-h bioassays were performed exposing organisms to different fenitrothion concentrations. The concentrations that induced 50 % inhibition of enzyme activity (EC50) were calculated. Fenitrothion bioavailability was investigated using different concentrations of commercial HA or particulate matter. Sand and a diverse selection of chromatographic resins that have been proposed as analogues of natural sediments were selected. For these experiments, animals were exposed to a fenitrothion value similar to the EC50.Results and discussion
The 48-h EC50 values were 12?±?2 and 23?±?3 μg?l?1 for L. variegatus and B. glabrata, respectively. Depending on HA concentration and the characteristics of particles, ChE activity was similar or higher than the value recorded for animals exposed only to the pesticide in aqueous solution.Conclusion
The results indicated that L. variegatus was the more sensitive species of the two. In this species, fenitrothion bioavailability did not increase due to the presence of either different HA concentrations or particulate matter. The experimental approach may constitute a useful tool to predict the influence of dissolved organic matter and sediment particles on fenitrothion bioavailability and toxicity to non-target aquatic invertebrates. 相似文献46.
Gustavo A. Castellanos‐Galindo Jaime R. Cantera Silvana Espinosa Luz Marina Mejía‐Ladino 《水产资源保护:海洋与淡水生态系统》2011,21(1):37-48
- 1. The loss of marine biodiversity in tropical regions of the world is a major threat to human welfare. Multiple anthropogenic drivers are responsible for this situation, with complex scenarios for coastal areas in third‐world countries, where economic development often competes with conservation plans.
- 2. The International Union for the Conservation of Nature (IUCN) Red List of Threatened Species is an influential tool for setting conservation priorities at local and regional levels. The application of IUCN criteria for assessing extinction risk, however, continues to represent a major challenge in data‐poor situations present in many tropical megadiverse countries.
- 3. To overcome these difficulties, three different data sources on invertebrates and fishes present in an estuarine system representative of the tropical eastern Pacific (TEP) region (Bahía Málaga, Colombia) have been used to establish their relative local extinction risk and correlate this information with the existing IUCN Red List categories. Data sources included (1) IUCN global and national listings, (2) traditional ecological knowledge (TEK), and (3) grey literature, scientific and natural history observations.
- 4. In total, 46 threatened species were evaluated after combining the three data sources. Only 17 species were previously identified as threatened by IUCN global and national listings, whereas the remaining 29 species were classified under a threatened category after evaluating TEK, grey literature and scientific information. Some of these species are seriously threatened within the estuary because of overharvesting and habitat destruction.
- 5. Despite most of the species identified having large geographical ranges in the TEP, they may face the same threats throughout their ranges. The approach provides a useful tool to assess species extinction risk in tropical regions where resource exploitation and habitat degradation advance rapidly, making the setting of conservation priorities an urgent task. Copyright © 2011 John Wiley & Sons, Ltd.
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Clare Greathead Paolo Magni Jan Vanaverbeke Lene Buhl‐Mortensen Urszula Janas Mats Blomqvist Johan A. Craeymeersch Jennifer Dannheim Alexander Darr Steven Degraer Nicolas Desroy Annick Donnay Yessica Griffiths Ivan Guala Laurent Guerin Hayley Hinchen Celine Labrune Henning Reiss Gert Van Hoey Silvana N.R. Birchenough 《水产资源保护:海洋与淡水生态系统》2020,30(7):1253-1275
- There is concern across the International Council for the Exploration of the Sea (ICES) region that a consideration of vulnerable components and the wider support mechanisms underpinning benthic marine ecosystems may be lacking from the process of marine protected area (MPA) designation, management and monitoring.
- In this study, MPAs across six European ecoregions were assessed from a benthic ecology perspective. The study included 102 MPAs, designated by 10 countries, and focused on three aspects regarding the role of the benthos in: (i) the designation of MPAs; (ii) the management measures used in MPAs; and (iii) the monitoring and assessment of MPAs.
- Qualitative entries to a questionnaire based on an existing framework (EU project ‘Monitoring Evaluation of Spatially Managed Areas’, (MESMA) were collected by 19 benthic experts of the ICES Benthic Ecology Working Group. A pedigree matrix was used to apply a numerical scale (score) to these entries.
- The results showed clear differences in scores between ecoregions and between criteria. The designation‐phase criteria generally achieved higher scores than the implementation‐phase criteria. Poor designation‐phase scores were generally reiterated in the implementation‐phase scores, such as scores for assessment and monitoring.
- Over 70% of the MPA case studies were found to consider the benthos to some extent during selection and designation; however, this was not followed up with appropriate management measures and good practice during the implementation phase.
- Poor spatial and temporal coverage of monitoring and ineffective indicators is unlikely to pick up changes caused by management measures in the MPA. There is concern that without adequate monitoring and adaptive management frameworks, the MPAs will be compromised. Also, there could be an increased likelihood that, with regard to the benthos, they will fail to meet their conservation objectives.
- This assessment was successful in highlighting issues related to the representation and protection of the benthos in MPAs and where changes need to be made, such as expanding the characterization and monitoring of benthic species or habitats of interest. These issues could be attributable to an ongoing process and/or an indication that some MPAs only have ‘paper protection’.
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Consalter Rangel Motta Antônio Carlos Vargas Barbosa Julierme Zimmer Vezzani Fabiane Machado Rubilar Rafael Alejandro Prior Stephen A. Nisgoski Silvana Bassaco Marcos Vinícius Martins 《European Journal of Forest Research》2021,140(5):1095-1112
European Journal of Forest Research - Brazil has extensive areas planted with Pinus taeda L. primarily in southern areas with poor soil fertility and nutritional management. Identifying optimal... 相似文献
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Martha Reyes‐Becerril Felipe Ascencio‐Valle José Meseguer Silvana Teresa Tapia‐Paniagua Miguel Angel Moriñigo María Ángeles Esteban 《Aquaculture Research》2012,43(8):1107-1118
This study evaluates the effects of the dietary administration of the live yeast Debaryomyces hansenii strain L2 on the immune responses of gilthead seabream for 4 weeks. Cellular immune parameters were measured from serum and head‐kidney leucocytes respectively. The expression levels of immune‐associated genes were quantified by real‐time polymerase chain reaction. In addition, the profile of intestinal microbiota was studied by denaturing gradient gel electrophoresis. The results showed that seabream fed a diet containing D. hansenii had significantly increased cellular immune parameters. The yeast‐supplemented diet up‐regulated the expression of most seabream genes at week 2 and down‐regulated all of them at week 4, except in the head‐kidney. Finally, a reduction in the diversity of the intestinal microbiota was detected in those specimens receiving the yeast‐supplemented diet. These results support the idea that the live yeast D. hansenii strain L2 stimulates the immune system of gilthead seabream. 相似文献
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Pistocchi R Guerrini F Pezzolesi L Riccardi M Vanucci S Ciminiello P Dell'Aversano C Forino M Fattorusso E Tartaglione L Milandri A Pompei M Cangini M Pigozzi S Riccardi E 《Marine drugs》2012,10(1):140-162
The Northern Adriatic Sea is the area of the Mediterranean Sea where eutrophication and episodes related to harmful algae have occurred most frequently since the 1970s. In this area, which is highly exploited for mollusk farming, the first occurrence of human intoxication due to shellfish consumption occurred in 1989, nearly 10 years later than other countries in Europe and worldwide that had faced similar problems. Until 1997, Adriatic mollusks had been found to be contaminated mostly by diarrhetic shellfish poisoning toxins (i.e., okadaic acid and dinophysistoxins) that, along with paralytic shellfish poisoning toxins (i.e., saxitoxins), constitute the most common marine biotoxins. Only once, in 1994, a toxic outbreak was related to the occurrence of paralytic shellfish poisoning toxins in the Adriatic coastal waters. Moreover, in the past 15 years, the Adriatic Sea has been characterized by the presence of toxic or potentially toxic algae, not highly widespread outside Europe, such as species producing yessotoxins (i.e., Protoceratium reticulatum, Gonyaulax spinifera and Lingulodinium polyedrum), recurrent blooms of the potentially ichthyotoxic species Fibrocapsa japonica and, recently, by blooms of palytoxin-like producing species of the Ostreopsis genus. This review is aimed at integrating monitoring data on toxin spectra and levels in mussels farmed along the coast of the Emilia-Romagna region with laboratory studies performed on the species involved in the production of those toxins; toxicity studies on toxic or potentially toxic species that have recently appeared in this area are also reviewed. Overall, reviewed data are related to: (i) the yessotoxins producing species P. reticulatum, G. spinifera and L. polyedrum, highlighting genetic and toxic characteristics; (ii) Adriatic strains of Alexandrium minutum, Alexandrium ostenfeldii and Prorocentrum lima whose toxic profiles are compared with those of strains of different geographic origins; (iii) F. japonica and Ostreopsis cf. ovata toxicity. Moreover, new data concerning domoic acid production by a Pseudo-nitzschia multistriata strain, toxicity investigations on a Prorocentrum cf. levis, and on presumably ichthyotoxic species, Heterosigma akashiwo and Chattonella cf. subsalsa, are also reported. 相似文献