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251.
252.
N. Seraphim M. A. Barreto G. S. S. Almeida A. P. Esperanço R. F. Monteiro A. P. Souza A. V. L. Freitas K. L. Silva-Brandão 《Conservation Genetics》2016,17(3):533-546
Parides ascanius (Lepidoptera: Papilionidae) is a butterfly endemic to the sand forests (“restingas”) of one of the most populated areas of Brazil (from Rio de Janeiro state to South Espírito Santo state), and was the first invertebrate officially recognized as being threatened in Brazil. Here we present a panel of eight polymorphic microsatellite loci and partial sequences of mitochondrial gene COI aiming to characterize this butterfly’s genetic diversity and understand its distribution among the extant populations. We estimate FST metrics, migration rates, cluster assignment, and spatial structure of genetic diversity. FST and statistics indicate low genetic structure and no evidence for endogamy, with all populations connected by high migration rates. Seven populations have low permanence rates (68–75 %) with increased migration probabilities for all populations. One population displays higher permanence rate (87.7 %), as the metropolitan matrix isolates it. Spatial analysis shows a global structure around the city of Rio de Janeiro and the Guanabara Bay; assignment analysis recovers six clusters evenly spread among sampled populations. These findings are consistent with a natural scenario of metapopulation dynamics for P. ascanius, with low genetic diversity and no endogamy, but progressively isolated by the metropolitan matrix. Conservation efforts should focus in connecting the isolated population, broaden the searches for new populations, and preserve all extant habitat patches where P. ascanius still occurs. 相似文献
253.
Habib Yaribeygi Stephen L. Atkin Luis E. Simental-Mendía George E. Barreto Amirhossein Sahebkar 《Journal of cellular physiology》2019,234(9):14873-14882
The incidence of diabetes mellitus is growing rapidly. The exact pathophysiology of diabetes is unclear, but there is increasing evidence of the role of the inflammatory response in both developing diabetes as well as its complications. Resolvins are naturally occurring polyunsaturated fatty acids that are found in fish oil and sea food that have been shown to possess anti-inflammatory actions in several tissues including the kidneys. The pathways by which resolvins exert this anti-inflammatory effect are unclear. In this review we discuss the evidence showing that resolvins can suppress inflammatory responses via at least five molecular mechanisms through inhibition of the nucleotide-binding oligomerization domain protein 3 inflammasome, inhibition of nuclear factor κB molecular pathways, improvement of oxidative stress, modulation of nitric oxide synthesis/release and prevention of local and systemic leukocytosis. Complete understanding of these molecular pathways is important as this may lead to the development of new effective therapeutic strategies for diabetes and diabetic nephropathy. 相似文献
254.
Juliana Saraiva Claudia Meirelles Siqueira Carlos Henrique Tomich de Paula da Silva Vinicius Barreto da Silva Valeria Gomes Tudella Rosângela Silva 《Journal of enzyme inhibition and medicinal chemistry》2013,28(2):599-606
The effects on mitochondrial respiration and complex I NADH oxidase activity of cubebin and derivatives were evaluated. The compounds inhibited the state 3 glutamate/malate-supported respiration of hamster liver mitochondria with IC50 values ranging from 12.16 to 83.96 μM. NADH oxidase reaction was evaluated in submitochondrial particles. The compounds also inhibited this activity, showing the same order of potency observed for effects on state 3 respiration, as well as a tendency towards a non-competitive type of inhibition (KI values ranging from 0.62 to 16.1 μM). A potential binding mode of these compounds with complex I subunit B8, assessed by docking calculations, is proposed. 相似文献
255.
Eskandar Taghizadeh Mehdi Rezaee George E. Barreto Amirhossein Sahebkar 《Journal of cellular physiology》2019,234(6):7874-7884
Limb-girdle muscular dystrophies (LGMDs) are a highly heterogeneous group of neuromuscular disorders that are associated with weakness and wasting of muscles in legs and arms. Signs and symptoms may begin at any age and usually worsen by time. LGMDs are autosomal disorders with different types and their prevalence is not the same in different areas. New technologies such as next-generation sequencing can accelerate their diagnosis. Several important pathological mechanisms that are involved in the pathology of the LGMD include abnormalities in dystrophin–glycoprotein complex, the sarcomere, glycosylation of dystroglycan, vesicle and molecular trafficking, signal transduction pathways, and nuclear functions. Here, we provide a comprehensive review that integrates LGMD clinical manifestations, prevalence, and some pathological mechanisms involved in LGMDs. 相似文献
256.
257.
Aims
We evaluated the mechanisms involved in insulin-induced vasodilatation after acute resistance exercise in healthy rats.Main methods
Wistar rats were divided into 3 groups: control (CT), electrically stimulated (ES) and resistance exercise (RE). Immediately after acute RE (15 sets with 10 repetitions at 70% of maximal intensity), the animals were sacrificed and rings of mesenteric artery were mounted in an isometric system. After this, concentration–response curves to insulin were performed in control condition and in the presence of LY294002 (PI3K inhibitor), L-NAME (NOS inhibitor), L-NAME + TEA (K+ channels inhibitor), LY294002 + BQ123 (ET-A antagonist) or ouabain (Na+/K+ ATPase inhibitor).Key findings
Acute RE increased insulin-induced vasorelaxation as compared to control (CT: Rmax = 7.3 ± 0.4% and RE: Rmax = 15.8 ± 0.8%; p < 0.001). NOS inhibition reduced (p < 0.001) this vasorelaxation from both groups (CT: Rmax = 2.0 ± 0.3%, and RE: Rmax = − 1.2 ± 0.1%), while PI3K inhibition abolished the vasorelaxation in CT (Rmax = − 0.1 ± 0.3%, p < 0.001), and caused vasoconstriction in RE (Rmax = − 6.5 ± 0.6%). That insulin-induced vasoconstriction on PI3K inhibition was abolished (p < 0.001) by the ET-A antagonist (Rmax = 2.9 ± 0.4%). Additionally, acute RE enhanced (p < 0.001) the functional activity of the ouabain-sensitive Na+/K+ ATPase activity (Rmax = 10.7 ± 0.4%) and of the K+ channels (Rmax = − 6.1 ± 0.5%; p < 0.001) in the insulin-induced vasorelaxation as compared to CT.Significance
Such results suggest that acute RE promotes enhanced insulin-induced vasodilatation, which could act as a fine tuning to vascular tone. 相似文献258.
Thiago Acosta Oliveira Gessi Koakoski Adriana Costa da Motta Angelo Luis Piato Rodrigo Egydio Barreto Gilson Luiz Volpato Leonardo José Gil Barcellos 《Hormones and behavior》2014
Living animals exploit information released from dead animals to conduct adaptive biological responses. For instance, a recently published study has shown that avoidance behavior is triggered by death-associated odors in zebrafish. Stress can clearly act as an adaptive response that allows an organism to deal with an imminent threat. However, it has not been demonstrated whether these chemical cues are stressful for fish. Here, we confirmed that dead zebrafish scents induce defensive behavior in live conspecifics. Additionally, we show for the first time in fish that these scents increase cortisol in conspecifics. To reach this conclusion, firstly, we exposed zebrafish to multi-sensorial cues (e.g., visual, tactile, chemical cues) from dead conspecifics that displayed defensive behaviors and increased cortisol. Also, when we limited zebrafish to chemical cues from dead conspecifics, similar responses arose. These responses coincide with the decaying destruction of epidermal cells, indicating that defensive and stress responses could take place as an effect of substances emanating from decaying flesh, as well as alarm substance released due to rupture of epidermal cells. Taken together, these results illustrate that living zebrafish utilize cues from dead conspecific to avoid or to cope with danger and ensure survival. 相似文献
259.
K. M. Ribeiro B. Barreto M. Pasqual P. J. White R. A. Braga L. X. Dupuy 《Annals of botany》2014,113(3):555-563
Background and Aims
Shining a laser onto biological material produces light speckles termed biospeckles. Patterns of biospeckle activity reflect changes in cell biochemistry, developmental processes and responses to the environment. The aim of this work was to develop methods to investigate the biospeckle activity in roots and to characterize the distribution of its intensity and response to thigmostimuli.Methods
Biospeckle activity in roots of Zea mays, and also Jatropha curcas and Citrus limonia, was imaged live and in situ using a portable laser and a digital microscope with a spatial resolution of 10 μm per pixel and the ability to capture images every 0·080 s. A procedure incorporating a Fujii algorithm, image restoration using median and Gaussian filters, image segmentation using maximum-entropy threshold methods and the extraction of features using a tracing algorithm followed by spline fitting were developed to obtain quantitative information from images of biospeckle activity. A wavelet transform algorithm was used for spectral decomposition of biospeckle activity and generalized additive models were used to attribute statistical significance to changes in patterns of biospeckle activity.Key Results
The intensity of biospeckle activity was greatest close to the root apex. Higher frequencies (3–6 Hz) contributed most to the total intensity of biospeckle activity. When a root encountered an obstacle, the intensity of biospeckle activity decreased abruptly throughout the root system. The response became attenuated with repeated thigmostimuli.Conclusions
The data suggest that at least one component of root biospeckle activity resulted from a biological process, which is located in the zone of cell division and responds to thigmostimuli. However, neither individual cell division events nor root elongation is likely to be responsible for the patterns of biospeckle activity. 相似文献260.
Aline Teixeira Amorim Lucas Miranda Marques Angelita Maria Oliveira Gusm?o Santos Hellen Braga Martins Maysa Santos Barbosa Izadora Souza Rezende Ewerton Ferraz Andrade Guilherme Barreto Campos Tássia Neves Lob?o Beatriz Araujo Cortez Telma Alvez Monezi Glaucia Maria Machado-Santelli Jorge Timenetsky 《Biological research》2014,47(1)