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651.
Helena B. Nader Helio K. Takahashi Jorge A. Guimares Carl P. Dietrich Pietro Bianchini Bruna Ozima 《International journal of biological macromolecules》1981,3(6):356-360
A comparative study of heparin fractions obtained by affinity chromatography, electrofocusing, selective barium precipitation, polyacrylamide and agarose gel electrophoresis is reported. It is concluded that commercial heparin preparations are heterogeneous, containing at least 120 components which differ in molecular weight, in degree of affinity for antithrombin, and in their distribution in monomeric and dimeric forms. High anticoagulant activity for some heparin fractions was obtained by most of the methods used. 相似文献
652.
Filho Robério Freire de Castro Carla Soraia Soares Casanova Catarina Bezerra Bruna Martins 《Primates; journal of primatology》2021,62(5):777-788
Primates - Humans have used non-human primates (hereafter referred to as primates) as food source, medicine, parts of rituals, pets, and models for various studies worldwide. Here we investigated... 相似文献
653.
AbstractCandida species are fungal opportunistic pathogens capable of colonizing and infecting various human anatomical sites, where they have to adapt to distinct niche-specific pH conditions. The aim of this study was to analyse the features of Candida albicans and Candida glabrata biofilms developed under neutral and vaginal acidic (pH 4) conditions. C. albicans produced thicker and more filamentous biofilms under neutral than under acidic conditions. On the other hand, the formation of biofilms by C. glabrata was potentiated by the acidic conditions suggesting the high adaptability of this species to the vaginal environment. In general, both species developed biofilms containing higher amounts of matrix components (protein and carbohydrate) under neutral than acidic conditions, although the opposite result was found for one C. glabrata strain. Overall, this study contributes to a better understanding of the modulation of C. albicans and C. glabrata virulence by specific pH conditions. 相似文献
654.
655.
Pedro Eliel Marcio da Rosa Franchi Santos Lorena Flor Scavuzzi Bruna Miglioranza Iriyoda Tatiana Mayumi Veiga Peixe Tiago Severo Lozovoy Marcell Alysson Batiste Reiche Edna Maria Vissoci Dichi Isaias Simão Andréa Name Colado Santos Maria Josefa 《Biological trace element research》2019,191(1):34-44
Biological Trace Element Research - Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease of multifactorial origin. Studies have shown that trace elements such as zinc and... 相似文献
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657.
Adrian A. Barnett Anita I. Stone Peter Shaw Beatriz Ronchi-Teles Tereza dos Santos-Barnett Natalia C. Pimenta Natalia M. Kinap Wilson R. Spironello Aparecida Bitencourt Gemma Penhorwood Rebecca N. Umeed Tadeu G. de Oliveira Bruna M. Bezerra Sarah A. Boyle Caroline Ross John W. Wenzel 《Austral ecology》2023,48(4):719-742
Optimal foraging theory predicts that well-defended potential foods should be exploited only when energy pay-offs are great. Although stinging hymenopteran nests are both well-defended and predated by primates, their larvae's energy yields rarely have been calculated, and predation-linked foraging behaviours by primates infrequently documented. Based on 58 opportunistic observations of primates raiding wasp nests for larvae, we calculated energetic yields of low- and high-risk wasp nest predation for Cebus albifrons, Saimiri collinsi, S. sciureus and Sapajus apella, and tested predictions derived from optimal foraging theory. We recorded how nests were processed and by which age-sex classes, eaten nest fragment sizes, number of occupied and empty cells, and nest occupancy patterns (percent larvae/pupae, eggs, empty cells). Basal metabolic rate (BMR) calculations showed energetic yields from 15 min foraging on low-risk nests (Polybia quadricincta) would meet energy needed to sustain adult female and male C. albifrons BMR for 4.9 and 4.5 h, respectively; yields from high-risk (Chartergus artifex) nests for 6.5 and 6.2 h; Mischocyttarus sp. nest yields (low risk, but mimetically resembling other wasps) would meet S. collinsi BMR for 2.9 h (female) and 2.3 h (male), and 2.6 and 2.1 h, for the slightly larger S. sciureus, respectively. The Chartergus energetic-yield value is nearly 20% of a 36 g chocolate bar (741 kJ). Our data provide quantitative support for the common assertion that wasp larvae and pupae are high-yield foods for primates. As predicted by optimal foraging, energetic yield is sufficient to offset the risk and pain of being stung. 相似文献
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659.
Susie Andrade Bruno D. Arbo Bruna A. M. Batista Alice M. Neves Gisele Branchini Ilma S. Brum Helena M. T. Barros Rosane Gomez Maria Flavia M. Ribeiro 《Cell biochemistry and function》2012,30(8):696-700
Progesterone is a neuroactive hormone with non‐genomic effects on GABAA receptors (GABAAR). Changes in the expression of GABAAR subunits are related to depressive‐like behaviors in rats. Moreover, sex differences and depressive behaviors have been associated with prefrontal brain asymmetry in rodents and humans. Thus, our objective was to investigate the effect of progesterone on the GABAAR α1 and γ2 subunits mRNA expression in the right and left prefrontal cortex of diestrus female and male rats exposed to the forced swimming test (FST). Male and female rats (n = 8/group) were randomly selected to receive a daily dose of progesterone (0·4 mg·kg–1) or vehicle, during two complete female estrous cycles (8–10 days). On the experiment day, male rats or diestrus female rats were euthanized 30 min after the FST. Our results showed that progesterone significantly increased the α1 subunit mRNA in both hemispheres of male and female rats. Moreover, there was an inverse correlation between depressive‐like behaviors and GABAAR α1 subunit mRNA expression in the right hemisphere in female rats. Progesterone decreased the GABAAR γ2 mRNA expression only in the left hemisphere of male rats. Therefore, we conclude that the GABAA system displays an asymmetric distribution according to sex and that progesterone, at lower doses, presents an antidepressant effect after increasing the GABAAR α1 subunit expression in the right prefrontal cortex of female rats. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
660.
Junio Tavares Amaro Adeney de Freitas Bueno Pedro Manuel Oliveira Janeiro Neves Débora Mello da Silva Aline Pomari-Fernandes Bruna Magda Favetti 《Revista Brasileira de Entomologia》2018,62(3):195-197
The selectivity of five entomopathogens and a chemical insecticide (positive control) to pupae and adults of the egg parasitoid Telenomus remus (Nixon) was evaluated in the laboratory under controlled environmental conditions according to protocols established by the International Organization for Biological Control. Baculovirus anticarsia (Baculovirus AEE®), Bacillus thuringiensis var. kurstaki (Thuricide®), Bacillus thuringiensis var. aizawai (Agree®), Beauveria bassiana (Boveril®), Metarhizium anisopliae (Metarril®) and Trichoderma harzianum (Trichodermil®) are harmless to T. remus pupae, and adults. Thus, our results suggest that the insect control strategies applied here are compatible since entomopathogens were classified as harmless to T. remus in most examined cases and therefore facilitate a joint application to control different pests. Bacillus thuringiensis var. kurstaki (Dipel®), despite being classified as slightly harmful in some of the evaluations, can still be considered compatible for use together with T. remus, especially when compared with chemical insecticides such as chlorpyrifos that might be considered harmful to the parasitoid survival. 相似文献