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951.
Henrique Grande Sergio de M. Rezende Thiony E. Simon Fabiana C. Félix-Hackradt José A. García-Charton Mauro Maida Ana L. B. Gaspar Ronaldo B. Francini-Filho Thierry Fredou Beatrice P. Ferreira 《Journal of fish biology》2019,94(2):210-222
This study reports the results of 5 years of monitoring reef fish post-larvae using light traps in the Bay of Tamandaré, north-east Brazil. An annotated checklist of pre-settlement fish species, their frequency of occurrence and taxonomic characteristics are provided. In total, 4,422 post-larval fishes belonging to 36 families, 56 genera and 76 species were captured. The most species-rich families were Carangidae (7), Lutjanidae (6) and Pomacentridae (4), while the families Gerreidae (30.47%), Holocentridae (16.54%), Blenniidae (12.01%), Labrisomidae (8.36%), Lutjanidae (8.29%) and Acanthuridae (5.95%) were the most abundant. This is the first study of the taxonomic diversity and assemblage structure of settlement-stage reef fishes in the tropical south-west Atlantic Ocean. Although a few common species were not captured due to selectivity of light traps, the composition and taxonomic diversity of this first collection suggests that light traps are useful for studies of the early life history of a wide range of pre-settlement reef fishes. 相似文献
952.
Justin C. Bagley Pedro De Podestà Uchôa de Aquino María Florencia Breitman Francisco Langeani Guarino R. Colli 《Journal of fish biology》2019,95(4):1046-1060
The extraordinary species diversity of the Neotropical freshwater fish fauna is world renown. Yet, despite rich species diversity, taxonomic and genetic resources for its Cerrado ichthyofauna remain poorly developed. We provide a reference library of 149 DNA barcodes for 39 species/lineages of Cerrado headwater stream fishes from the Brazilian Distrito Federal and nearby areas and test the utility of distance-based criteria, tree-based criteria and minibarcodes for specimen identification. Mean Kimura 2-parameter genetic distances within species to orders ranged 1·8–12·1%. However, mean intraspecific v. congeneric-interspecific distances (0·9–1·3%) overlapped extensively and distance-based barcoding failed to achieve correct identifications due to c. 4–12·1% error rates and 19·5% ambiguous identifications related to the presence of singletons. Overlap was reduced and best-match success rates improved drastically to 83·5% when Characidium barcodes representing potential misidentifications or undescribed species were removed. Tree-based monophyly criteria generally performed similarly to distance methods, correctly differentiating up to c. 85% of species/lineages despite neighbour-joining and Bayesian tree errors (random lineage-branching events, long-branch attraction). Five clusters (Ancistrus aguaboensis, Characidium spp., Eigenmannia trilineata, Hasemania hanseni and Hypostomus sp. 2) exhibited deep intraspecific divergences or para−/polyphyly and multiple Barcode Index Number assignments indicative of putative candidate species needing taxonomic re-examination. Sliding-window analyses also indicated that a 200 bp minibarcode region performed just as well at specimen identification as the entire barcode gene. Future DNA barcoding studies of Distrito Federal–Cerrado freshwater fishes will benefit from increased sampling coverage, as well as consideration of minibarcode targets for degraded samples and next-generation sequencing. 相似文献
953.
Pedro Cisternas Juan M. Zolezzi Milka Martinez Viviana I. Torres Guang William Wong Nibaldo C. Inestrosa 《Journal of neurochemistry》2019,149(1):54-72
Dysregulated Wnt signaling is linked to major neurodegenerative diseases, including Alzheimer disease (AD). In mouse models of AD, activation of the canonical Wnt signaling pathway improves learning/memory, but the mechanism for this remains unclear. The decline in brain function in AD patients correlates with reduced glucose utilization by neurons. Here, we test whether improvements in glucose metabolism mediate the neuroprotective effects of Wnt in AD mouse model. APPswe/PS1dE9 transgenic mice were used to model AD, Andrographolide or Lithium was used to activate Wnt signaling, and cytochalasin B was used to block glucose uptake. Cognitive function was assessed by novel object recognition and memory flexibility tests. Glucose uptake and the glycolytic rate were determined using radiotracer glucose. The activities of key enzymes of glycolysis such as hexokinase and phosphofructokinase, Adenosine triphosphate (ATP)/Adenosine diphosphate (ADP) levels and the pentose phosphate pathway and activity of glucose‐6 phosphate dehydrogenase were measured. Wnt activators significantly improved brain glucose utilization and cognitive performance in transgenic mice. Wnt signaling enhanced glucose metabolism by increasing the expression and/or activity of hexokinase, phosphofructokinase and AMP‐activated protein kinase. Inhibiting glucose uptake partially abolished the beneficial effects of Wnt signaling on learning/memory. Wnt activation also enhanced glucose metabolism in cortical and hippocampal neurons, as well as brain slices derived from APPswe/PS1E9 transgenic mice. Combined, these data provide evidence that the neuroprotective effects of Wnt signaling in AD mouse models result, at least in part, from Wnt‐mediated improvements in neuronal glucose metabolism. 相似文献
954.
955.
del Cerro Pablo Ayala-García Paula Jiménez-Guerrero Irene López-Baena Francisco Javier Vinardell José María Megías Manuel Hungria Mariangela Gil-Serrano Antonio M. Pérez-Montaño Francisco Ollero Francisco Javier 《Plant and Soil》2019,434(1-2):185-201
Plant and Soil - Previous studies have shown that pH, rather than calcium (Ca), is the main reason why some Lupinus species are sensitive to nutrient solutions mimicking calcareous soils; however,... 相似文献
956.
Alirya Magda Santos do Vale Gomes Fabrício de Oliveira Reis Raimunda Nonata Santos de Lemos Janaína Marques Mondego Heder Braun José Ribamar Gusmão Araujo 《Revista Brasileira de Entomologia》2019,63(2):119-123
Aleurocanthus woglumi (Ashby, 1915) is an important agricultural pest that causes yield losses of 20–80% in citrus plants by removing plant nutrients while feeding and allowing the formation of sooty mold. The objective of this study was to evaluate physiological changes in citrus plants in response to A. woglumi infestation under field conditions. The experiment was conducted in a citrus orchard in Paço do Lumiar, Maranhão, Brazil. Thirty-two citrus plants were used, including eight of each of the following varieties: Tahiti lime, Tanjaroa tangerine, Nissey tangerine, and Ponkan tangerine. Four random plants with A. woglumi infestation and four plants free from this pest were selected from each variety. The physiological parameters evaluated were photochemical efficiency and gas exchange. Regarding photochemical efficiency, infested plants presented photoinhibition damage, with a performance index of 4.22. The gas exchange parameters of infested plants changed, with reductions in photosynthetic CO2 assimilation of 69.7% (Tahiti), 64% (Tanjaroa), 68.8% (Nissey) and 63.3% (Ponkan). Plants infested with A. woglumi also presented physiological changes; their photosynthetic CO2 assimilation, stomatal conductance, instantaneous transpiration, and performance indexes were affected. The infested citrus plants showed photoinhibition of photosystem II. The photosynthetic CO2 assimilation decreased approximately 70% in Tahiti lime, Tanjaroa tangerine, Nissey tangerine, and Ponkan tangerine plants infested with A. woglumi. 相似文献
957.
958.
Cortés-Ortiz Liliana Baiz Marcella D. Hermida-Lagunes Javier García-Orduña Francisco Rangel-Negrín Ariadna Kitchen Dawn M. Bergman Thore J. Dias Pedro A. D. Canales-Espinosa Domingo 《International journal of primatology》2019,40(1):114-131
International Journal of Primatology - Interspecific hybridization allows the introgression or movement of alleles from one genome to another. While some genomic regions freely exchange alleles... 相似文献
959.
Alberto De Jesús-Navarrete Frank Alberto Ocaña-Borrego José Juan Oliva-Rivera Rosa María De Jesús-Carrillo Abel Abraham Vargas-Espositos 《Studies on Neotropical Fauna and Environment》2019,54(1):1-9
Pomacea flagellata is a gastropod conspicuous in freshwater environments, and represents a fishing resource. To assess their abundance, distribution, and secondary production, monthly samplings were carried out in Bacalar Lake from June 2012 to May 2013 at 12 sampling sites. In each site, three random transects were marked parallel to the shore. All snails on transect were collected and shell length and wet weight measured. The highest density occurred in September (1.27 ind.m?2), lowest in October (0.47 ind.m?2). Shell lengths ranged from 2 to 56 mm, with recruitment in January–March. Growth parameters were L∞ 59.50 mm, K 0.65.year?1; the lifetime span was 3 years. Average biomass reached 5.57 wet g.m?2 and secondary production was 6.025 wet g.m?2.year-1; annual renewal rate P/B 1.08. Highest abundance and secondary production was contributed by individuals between 31 and 41 mm in length. A potential biomass of 25.06 tons of snails was estimated in the lake. Snail densities, secondary production, and turnover were very low during the year, indicating that it is not viable to consider a commercial catch without affecting the population. A ban of 10 years is proposed, and aquaculture practices of snails are recommended to recover the resource. 相似文献
960.
de Queiroz João Vitor Vieira José Cavalcante Souza de Oliveira Grasieli Braga Camila Pereira da Cunha Bataglioli Izabela da Silva Janaína Macedo de Paula Araújo Wellington Luiz de Magalhães Padilha Pedro 《Biological trace element research》2019,187(1):291-300
Biological Trace Element Research - Predator fish can accumulate high levels of mercury, which qualifies them as potential indicators of this toxic metal. The predatory species Brachyplatystoma... 相似文献