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971.
Daniel Martins Bruno Menezes de Oliveira Alessandro dos Santos Farias Ricardo Shiniti Oka Horiuchi Cleyton Crepaldi Domingues Eneida de Paula Sérgio Marangoni Wagner Farid Gattaz Emmanuel Dias-Neto José Camillo Novello 《Briefings in Functional Genomics and Prot》2007,6(1):70-75
Protein extraction is the most important step to reveal a proteome by Two-Dimensional Gel Electrophoresis. Usually, the urea/thiourea based standard protein extraction buffer (SB) is combined with detergents with the aim of achieving better resolution and solubilization of different classes of proteins. In order to produce better gels and achieve the greatest spot resolution of Human Brain Proteins, comparisons using 2-DE of extracted proteins from Human Brain Frontal Cortex with SB constituents (7M Urea, 2M Thiourea and 100mM DTT) were made, using different detergent compositions in the buffer. SB preparations in combination with CHAPS and ASB-14 as well as with ASB-16 (reported for the first time in 2-DE experiments) have been tested. Our results confirm that the most efficient solubilizing solution for 2-DE analysis of cytosolic and membrane Human Brain Proteins is SB combined with 4% CHAPS and 2% ASB-14. 相似文献
972.
The spatial and temporal variation of macroinvertebrate assemblages was studied in two Portuguese commercial rice agroecosystems
under the effect of field management involving the application of pesticides and fertilizers. A faunal succession of organisms
was observed on both fields. Grazers were the first to colonize the paddies after a dry period when pesticides were applied,
followed by development into nymphs and by an increase in the abundance of the species after the application of fertilizers.
At the end of the season when no pesticides or fertilizers were applied, the communities changed with the presence of adult
predators as a result of an increase in prey. Insecticide application revealed specific taxa increase due to the lack of competition
with the target organism. Macroinvertebrates tended to prefer infested field margins with aquatic, submerged vegetation, revealing
a spatial distribution along the paddies. Two different sampling devices were used and proved necessary in documenting the
macroinvertebrate communities (grab for benthic and hand-net for pelagic organisms). 相似文献
973.
Gonçalves JR Faroni LR Guedes RN De Oliveira CR Garcia FM 《Neotropical Entomology》2007,36(2):247-253
The objective of this study was to evaluate the effect of different temperatures with the association of the mite Acarophenax lacunatus (Cross & Krantz) on the population suppression of Rhyzopertha dominica (Fabricius). The experimental units were petri dishes containing 40 g of whole wheat grains (13% moisture content) infested with 10 adults of R. dominica, under the temperatures of 20, 25, 30 and 35 masculineC, with or without A. lacunatus, in five replicates. Relative humidity of 60 +/- 5% and escotophase of 24h were used for all temperatures. Five days after the infestation, five mites were inoculated in each experimental unit. The evaluations were carried out at 20, 40, 60, 80, 100 and 120 days after R. dominica infestation. The interaction of the temperature with the parasite A. lacunatus was an important tool for the population suppression of R. dominica. In temperatures higher than 25 masculineC, however, despite the reduction of the immature stages of R. dominica, there was a high grain weight loss after 120 days. The maintenance of the temperature of the wheat grains stored at 20 masculineC can be used to complement the biological control of R. dominica with A. lacunatus. 相似文献
974.
Miyamoto S Ronsein GE Prado FM Uemi M Corrêa TC Toma IN Bertolucci A Oliveira MC Motta FD Medeiros MH Mascio PD 《IUBMB life》2007,59(4-5):322-331
The decomposition of lipid hydroperoxides (LOOH) into peroxyl radicals is a potential source of singlet molecular oxygen ((1)O(2)) in biological systems. Recently, we have clearly demonstrated the generation of (1)O(2) in the reaction of lipid hydroperoxides with biologically important oxidants such as metal ions, peroxynitrite and hypochlorous acid. The approach used to unequivocally demonstrate the generation of (1)O(2) in these reactions was the use of an isotopic labeled hydroperoxide, the (18)O-labeled linoleic acid hydroperoxide, the detection of labeled compounds by HPLC coupled to tandem mass spectrometry (HPLC-MS/MS) and the direct spectroscopic detection and characterization of (1)O(2) light emission. Using this approach we have observed the formation of (18)O-labeled (1)O(2) by chemical trapping of (1)O(2) with anthracene derivatives and detection of the corresponding labeled endoperoxide by HPLC-MS/MS. The generation of (1)O(2) was also demonstrated by direct spectral characterization of (1)O(2) monomol light emission in the near-infrared region (lambda = 1270 nm). In summary, our studies demonstrated that LOOH can originate (1)O(2). The experimental evidences indicate that (1)O(2) is generated at a yield close to 10% by the Russell mechanism, where a linear tetraoxide intermediate is formed in the combination of two peroxyl radicals. In addition to LOOH, other biological hydroperoxides, including hydroperoxides formed in proteins and nucleic acids, may also participate in reactions leading to the generation (1)O(2). This hypothesis is currently being investigated in our laboratory. 相似文献
975.
De Oliveira CR Faroni LR Guedes RN Gonçalves JR Garcia FM 《Neotropical Entomology》2007,36(3):459-464
The aim of the present study was to assess the effect of six different temperatures on the development of Acarophenax lacunatus (Cross & Krantz) using eggs of Tribolium castaneum (Herbst) and Cryptolestes ferrugineus (Stephens) as hosts. The temperature affected the development of A. lacunatus. The largest values for the progeny (19 mites in T. castaneum and 15 mites in C. ferrugineus) were obtained at about 30 degrees C, as also observed for the net reproductive rate (Ro), which revealed that the A. lacunatus population increased 18 times in T. castaneum and 14 times in C. ferrugineus in a generation. The intrinsic rate of increase (r m) gradually increased with temperature, reaching the maximum value at 35 degrees C in T. castaneum (1,608) and C. ferrugineus (1,289). The generation time was negatively correlated with temperature, ranging from 1,60 to 4,85 days in T. castaneum and from 1,96 to 5,34 days in C. ferrugineus. These results suggest that the mite A. lacunatus may be used in programs of biological control of T. castaneum and C. ferrugineus in the tropics. 相似文献
976.
The present study intended to verify which factors (phylogenetic relationship or local ecological conditions) would determine how Frieseomelitta bees use floral resources. The data obtained in the literature on biocenotic studies of Apoidea visiting flowers in Brazil were analyzed, with identification and quantification of floral resources used by Frieseomelitta species in different areas. The phenogram of similarity on use of resources among Frieseomelitta species was compared to the phylogenetic hypothesis proposed for the group. Among the eight Frieseomelitta species registered in 19 studies, F. doederleini (Friese), F. francoi (Moure), F. languida Moure, F. varia (Lepeletier) e Frieseomelitta sp. nov., were collected using resources from 36 plant families. F. doederleini, F. languida e F. varia centralized their activity in Caesalpiniaceae, Malpighiaceae e Anacardiaceae. The similarities and disparities found among areas and Frieseomelitta species reflected the similarities and differences of the vegetation composition in each area. Frieseomelitta bees presented a forage pattern similar to that one presented by other highly social bees, visiting flowers of many plant species, but concentrating their activities in few plant species. Despite the low phylogenetic relationship between F. languida and F. doederleini, they showed a high similarity on the use of floral resource, while F. varia e F. languida, species with high phylogenetic relationship, showed low similarity in the use of resource. Although the data obtained are not conclusive, it indicates that phylogenetic restrictions do not influence the pattern of use of floral resource by Frieseomelitta bees. 相似文献
977.
Martins Renato T. Brito Janaina Dias-Silva Karina Leal Ceclia G. Leito Rafael P. Oliveira Vivian C. Oliveira-Jnior Jos M. B. de Paula Felipe R. Roque Fabio O. Hamada Neusa Juen Leandro Nessimian Jorge L. Pompeu Paulo S. Hughes Robert M. 《Hydrobiologia》2022,849(10):2281-2298
Hydrobiologia - Stream degradation in Amazonia is outpacing our ability to effectively monitor it for three key reasons: (1) Many changes are cumulative and occur gradually; (2) Scientists have... 相似文献
978.
Bunholi Ingrid Vasconcellos da Silva Ferrette Bruno Lopes Domingues Rodrigo Rodrigues Rotundo Matheus Marcos Cuevas Juan Martín García Mirta Gómez Sebastián de Freitas Renato Hajenius Aché Oliveira Claudio Foresti Fausto Mendonça Fernando Fernandes 《Hydrobiologia》2022,849(9):2177-2192
Hydrobiologia - The angular angelshark (Squatina guggenheim) is a coastal endangered angel shark from the Southwest Atlantic Ocean and one of the major bycatch victims. Despite major concerns about... 相似文献
979.
Martins Renato Tavares de Freitas Silva Rafael Augusto Pinheiro Pinto Valria Arajo Braule Medeiros Adriana Oliveira Brito Laisa Hamada Neusa 《Hydrobiologia》2022,849(16):3531-3544
Hydrobiologia - We used experimental chambers to evaluate the effect of the temperature increasing and microbial conditioning degree on the survival and leaf consumption of two plant species... 相似文献
980.
Teixeira Gelza Carliane Marques de Mello Prado Renato de Oliveira Larissa Trinque de Castro Souza João Vitor Rocha Antonio Márcio Souza 《Plant and Soil》2022,477(1-2):83-97
Plant and Soil - The objective was to evaluate soluble sources of silicon (Si) applied through fertigation in mitigating water deficit in maize plants. Another objective was to determine the... 相似文献