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An adaptation of the Sols and Ponz method for the study of glucose intestinal absorption was developed by considering the special conditions of our line research. The glucose absorption was studied in proximal jejunum, distal ileum and distal colon in Wistar rat. The main adaptations in the method for successive absorptions with intestinal perfusions in vivo were the length of the intestinal segment and the change of the pumping system. The results are very similar to those obtained with the original method. 相似文献
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Paloma Rocha Arakaki Paula Andrea Borges Salgado Joo Diego de Agostini Losano Dbora Rodrigues Gonalves Rodrigo del Rio do Valle Ricardo Jos Garcia Pereira Marcilio Nichi 《American journal of primatology》2019,81(12)
Wild animal genetic resource banking (GRB) represents a valuable tool in conservation breeding programs, particularly in cases involving endangered species such as the golden‐headed lion tamarin (Leontopithecus chrysomelas). Thus, we aimed to assess a sperm freezing protocol for golden‐headed lion tamarins using two different exenders: BotuBOV® (BB) and Test Yolk Buffer® (TYB). Ejaculates were collected by penile vibrostimulation from animals housed at São Paulo Zoological Park Foundation, São Paulo, Brazil, and after immediate analysis, two aliquots were diluted in BB and TYB. Postthawing samples were evaluated for total and progressive motility, plasma membrane and acrosome integrities, mitochondrial activity, susceptibility to oxidative stress, and sperm–egg‐binding. No differences between BB and TYB were found for most seminal parameters, except for acrosome integrity and susceptibility to oxidative stress (in both cases BB showed higher values). However, in spite of these differences and regardless of the extender used, postthaw sperm motility and viability with the described protocol were encouraging (on average >50% and >80%, respectively), indicating that sperm cryopreservation may be a short‐term measure for the conservation of golden‐headed lion tamarins. 相似文献
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Elizabeth Nichols María Uriarte Carlos A. Peres Julio Louzada Rodrigo Fagundes Braga Gustavo Schiffler Whaldener Endo Sacha H. Spector 《PloS one》2013,8(10)
Human presence and activity in tropical forest is thought to exert top-down regulation over the various ‘green-world’ pathways of plant-based foodwebs. However, these effects have never been explored for the ‘brown-world’ pathways of fecal-detritus webs. The strong effects of humans on tropical game mammals are likely to indirectly influence fecal detritivores (including Scarabaeine dung beetles), with subsequent indirect impacts on detrivore-mediated and plant-facilitating detrital processes. Across a 380-km gradient of human influence in the western Brazilian Amazon, we conducted the first landscape-level assessment of human-induced cascade effects on the fecal detritus pathway, by coupling data on human impact, game mammal and detritivore community structure, and rate measurements of a key detritus process (i.e. dung beetle-mediated secondary seed dispersal). We found evidence that human impact indirectly influences both the diversity and biomass of fecal detritivores, but not detritivore-mediated processes. Cascade strength varied across detritivore groups defined by species'' traits. We found smaller-bodied dung beetles were at higher risk of local decline in areas of human presence, and that body size was a better predictor of cascade structure than fecal resource manipulation strategy. Cascade strength was also stronger in upland, unflooded forests, than in seasonally flooded forests. Our results suggest that the impact of human activity in tropical forest on fecal-detritus food web structure is mediated by both species'' traits and habitat type. Further research will be required to determine the conditions under which these cascade effects influence fecal-detritus web function. 相似文献
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Geisiane Amorim de Brito Paulo Fernando Rocha de Oliveira Caliene Melo de Andrade Silva Moysés Fagundes de Araújo Neto Franco Henrique Andrade Leite Paulo Roberto Ribeiro Mesquita Tiago Feitosa Mota Jairo Torres Magalhães-Junior 《化学与生物多样性》2021,18(9):e2100242
Most of the hematophagous insects act as disease vectors, including Aedes aegypti, responsible for transmitting some of the most critical arboviruses globally, such as Dengue. The use of repellents based on natural products is a promising alternative for personal protection compared to industrial chemical repellents. In this study, the repellent effect of essential oils extracted from Lippia thymoides, Lippia alba, Cymbopogon winterianus, and Eucalyptus globulus leaves was evaluated. Essential oils used showed repellent activity against Ae. aegypti in laboratory bioassays, obtaining protection rates above 70 % from 3.75 mg/mL and higher concentration for all analyzed oils. GC/MS identified 57 constituents, which were used in the ligand-based pharmacophore model to expose compounds with requirements for repellents that modulate mosquitoes behavior through odorant-binding protein 1 Ae. aegypti. Ligand-based pharmacophore model approach results suggested that repellent activity from C. winterianus, L. alba, and L. thymoides essential oils’ metabolites is related to Citronelal (QFIT=26.77), Citronelol (QFIT=11.29), Citronelol acetate (QFIT=52.22) and Geranil acetate (QFIT=10.28) with synergistic or individual activity. E. globulus essential oil's repellent activity is associated with Ledol (0.94 %; QFIT=41.95). Molecular docking was applied to understand the binding mode and affinity of the essential oils’ data set at the protein binding site. According to molecular docking, Citronelol (ChemPLP=60.98) and geranyl acetate (ChemPLP=60.55) were the best-classified compounds compared to the others and they can be explored to develop new repellents. 相似文献
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Fernanda Vieira da Costa Frederico de Siqueira Neves Jhonathan de Oliveira Silva Marc��lio Fagundes 《Arthropod-Plant Interactions》2011,5(1):9-18
Plant development is the main factor that determines the insect-ontogeny interaction, since it leads to variations in resource
quality and availability. The aim of this study was to test the hypothesis that plant development and varying tannin concentration
leads to changes in species richness, abundance and composition of ants, free-feeding herbivores and galling insects associated
with Copaifera langsdorffii (Fabaceae). The plant ontogeny and tannin concentration effects on insects were tested on 60 individuals with height varying from 0.9
to 11.0 m. A positive correlation was observed for tree height and species richness and abundance of ants, free-feeding and
galling insects. In contrast, we did not find a significant relation between leaf tannin concentration and plant height, or
richness and abundance of the different insect guilds. The assemblage of ants (composition of species) did not change between
saplings and adults of C. langsdorffii. However, the assemblage of free-feeding herbivores and galling insects varied between the two development stages studied.
The present study reveals an ontogenetic succession pattern for herbivore insects along the C. langsdorffii growth, probably due to both indirect and direct benefits from the host plant architecture and quality. Those plants with
more complex architectures should support a wider diversity of insects, since they present higher number of sites for egg
laying, housing, feeding and better environmental conditions. This is the first work to investigate the host plant ontogeny
effect on insects in Cerrado “Savanna” vegetation. The pattern described, along with other previous studies, suggests a vast
occurrence of ontogenetic succession in tropical areas. 相似文献
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Kerly Wollmeister Hofmann Artur Francisco Schumacher Schuh Jonas Saute Raquel Townsend Daniele Fricke Renata Leke Diogo O. Souza Luis Valmor Portela Márcia Lorena Fagundes Chaves Carlos R. M. Rieder 《Neurochemical research》2009,34(8):1401-1404
Several lines of evidence suggest that neuroimmune mechanisms may be involved in the neurodegenerative process of Parkinson’s
disease (PD). Interleukin-6 (IL-6) is increased in the nigrostriatal region and in the cerebrospinal fluid of patients with
PD. IL-6 serum level was evaluated in PD patients. The effects of levodopa treatment and disease severity on IL-6 were also
studied. The IL-6 levels were similar between PD patients (treated and not treated) and controls. However, there was a negative
correlation of IL-6 levels and the activities of daily living scale (P < 0.05), indicating that patients with more severe disease have higher levels of this cytokine. No correlation involving
levodopa treatment and IL-6 serum level was found. The results suggest that only marginal effects of IL-6 occur on the peripheral
immune system, and that the role of IL-6 and others neuroimmune factors needs to be well elucidated on PD. 相似文献
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Ricardo Fagundes da Rocha Marcos Roberto de Oliveira Matheus Augusto de Bittencourt Pasquali Michael Éverton Andrades Max William Soares Oliveira Guilherme Antônio Behr José Cláudio Fonseca Moreira 《Cell biochemistry and function》2010,28(3):190-196
Exercise training has been used for treatment/prevention of many cardiovascular diseases, but the mechanisms need to be clarified. Thus, our aim was to compare oxidative stress parameters between rats submitted to a swimming training and sedentary rats (control). Twelve male rats were divided into two groups: control and exercise training. The exercise training had daily 1 h swimming sessions for 8 weeks and a load (5% of its body mass) was placed in rat's tail. Thereafter the animals were killed, aorta and heart were surgically removed and blood was collected. Body mass gain, thiobarbituric acid reactive species (TBARS), carbonyl content, total reactive antioxidant potential (TRAP), total antioxidant reactivity (TAR), superoxide dismutase (SOD) activity and catalase (CAT) activity were evaluted. The trained rats showed a lower body mass gain and no modifications on heart. An increased SOD activity was observed on aorta after the training, but no changes were seen for CAT activity, which led to an increased SOD/CAT ratio. The arterial TBARS was also increased for trained rats. The decrease in TRAP in exercise training was the single modification on plasma. Our findings suggest that the increased SOD activity could play a role in vascular adaptations to exercise training. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Thiago Acosta Oliveira Gessi Koakoski Luiz Carlos Kreutz Daiane Ferreira Jo?o Gabriel Santos da Rosa Murilo Sander de Abreu Ana Cristina Vendrametto Giacomini Ricardo Pimentel Oliveira Michele Fagundes Angelo Luis Piato Rodrigo Egydio Barreto Leonardo José Gil Barcellos 《PloS one》2013,8(10)
The effects of ethanol exposure on Danio rerio have been studied from the perspectives of developmental biology and behavior. However, little is known about the effects of ethanol on the prey-predator relationship and chemical communication of predation risk. Here, we showed that visual contact with a predator triggers stress axis activation in zebrafish. We also observed a typical stress response in zebrafish receiving water from these conspecifics, indicating that these fish chemically communicate predation risk. Our work is the first to demonstrate how alcohol effects this prey-predator interaction. We showed for the first time that alcohol exposure completely blocks stress axis activation in both fish seeing the predator and in fish that come in indirect contact with a predator by receiving water from these conspecifics. Together with other research results and with the translational relevance of this fish species, our data points to zebrafish as a promising animal model to study human alcoholism. 相似文献