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951.
Silvio A. Oliveira-Junior Paula F. Martinez Danielle M. Guizoni Dijon H. S. Campos Tiago Fernandes Edilamar M. Oliveira Marina P. Okoshi Katashi Okoshi Carlos R. Padovani Antonio C. Cicogna 《PloS one》2014,9(1)
Background
Although obesity has been associated with metabolic and cardiac disturbances, the carrier mechanisms for these responses are poorly understood. This study analyzed whether angiotensin II blockade attenuates metabolic and cardiovascular disorders in rats with diet-induced obesity.Material and Methods
Wistar-Kyoto (n = 40) rats were subjected to control (C; 3.2 kcal/g) and hypercaloric diets (OB; 4.6 kcal/g) for 30 weeks. Subsequently, rats were distributed to four groups: C, CL, OB, and OBL. L groups received Losartan (30 mg/kg/day) for five weeks. After this period we performed in vivo glucose tolerance and insulin tolerance tests, and measured triacylglycerol, insulin, angiotensin-converting enzyme activity (ACE), and leptin levels. Cardiovascular analyzes included systolic blood pressure (SBP), echocardiography, myocardial morphometric study, myosin heavy chain composition, and measurements of myocardial protein levels of angiotensin, extracellular signal-regulated (ERK1/2), c-Jun amino-terminal kinases (JNK), insulin receptor subunit β (βIR), and phosphatidylinositol 3-kinase (PI3K) by Western Blot.Results
Glucose metabolism, insulin, lipid, and ACE activity disorders observed with obesity were minimized by Losartan. Moreover, obesity was associated with increased SBP, myocardial hypertrophy, interstitial fibrosis and improved systolic performance; these effects were also minimized with Losartan. On a molecular level, OB exhibited higher ERK, Tyr-phosphorylated βIR, and PI3K expression, and reduced myocardial angiotensin and JNK expression. ERK and JNK expression were regulated in the presence of Losartan, while angiotensin, Tyr-βRI, total and Tyr-phosphorylated PI3K expression were elevated in the OBL group.Conclusion
Angiotensin II blockade with Losartan attenuates obesity-induced metabolic and cardiovascular changes. 相似文献952.
Tiago de Souza Leite Andréia Cnossen-Fassoni Olinto Liparini Pereira Eduardo Seiti Gomide Mizubuti Elza Fernandes de Araújo Marisa Vieira de Queiroz 《Journal of microbiology (Seoul, Korea)》2013,51(1):56-69
Fungal endophytes were isolated from the leaves of soybean cultivars in Brazil using two different isolation techniques — fragment plating and the innovative dilution-to-extinction culturing — to increase the species richness, frequency of isolates and diversity. A total of 241 morphospecies were obtained corresponding to 62 taxa that were identified by analysis of the internal transcribed spacer (ITS) of the ribosomal DNA (rDNA). The Phylum Ascomycota predominated, representing 99% and 95.2% of isolates in the Monsoy and Conquista cultivars, respectively, whereas the Phylum Basidiomycota represented 1% and 4.8% of isolates, respectively. The genera Ampelomyces, Annulohypoxylon, Guignardia, Leptospora, Magnaporthe, Ophiognomonia, Paraconiothyrium, Phaeosphaeriopsis, Rhodotorula, Sporobolomyces, and Xylaria for the first time were isolated from soybean; this suggests that soybean harbours novel and highly diverse fungi. The yeasts genera Rhodotorula and Sporobolomyces (subphylum Pucciniomycotina) represent the Phylum Basidiomycota. The species richness was greater when both isolation techniques were used. The diversity of fungal endophytes was similar in both cultivars when the same isolation technique was used except for Hill’s index, N1. The use of ITS region sequences allowed the isolates to be grouped according to Order, Class and Phylum. Ampelomyces, Chaetomium, and Phoma glomerata are endophytic species that may play potential roles in the biological control of soybean pathogens. This study is one of the first to apply extinction-culturing to isolate fungal endophytes in plant leaves, thus contributing to the development and improvement of this technique for future studies. 相似文献
953.
Abstract The encouraging results obtained in a previous work induced the authors to pursue here the characterization of the structure of the vegetation in northern Portugal, using the phytostructural methodology proposed earlier by the authors. With this objective, eight different types of vegetal communities, representative of the apparent states of the successional process present in this area, and representing the diversity of plant community types in the same area, were selected. The phytostructural method was elaborated on the basis of three types of structural basic matrices regarding diversity, abundance and cover. The data obtained were collected in a contingency matrix, which was then treated by means of a statistical multivariate analysis. Three structural tendencies emerged from this analysis. With the aim of studying their stability, the results are discussed in terms of resistance and resilience, according to the Highest Expressive Amplitude (HEA) concept, and by considering the intra- and inter-community structural dynamics as structural parameters. The data obtained suggest structural situations with different degrees of non-equilibrium that reflect resistance to environmental factors. The resistance of the vegetation is correlated with the apparent functional connectivity detected for the communities analysed. 相似文献
954.
Luís Silva Sérgio Marta João Vaz Orlando Fernandes Maria António Castro Pedro Pezarat-Correia 《Journal of electromyography and kinesiology》2013,23(5):1174-1182
There is a lack of studies regarding EMG temporal analysis during dynamic and complex motor tasks, such as golf swing. The aim of this study is to analyze the EMG onset during the golf swing, by comparing two different threshold methods. Method A threshold was determined using the baseline activity recorded between two maximum voluntary contraction (MVC). Method B threshold was calculated using the mean EMG activity for 1000 ms before the 500 ms prior to the start of the Backswing. Two different clubs were also studied. Three-way repeated measures ANOVA was used to compare methods, muscles and clubs. Two-way mixed Intraclass Correlation Coefficient (ICC) with absolute agreement was used to determine the methods reliability.Club type usage showed no influence in onset detection. Rectus abdominis (RA) showed the higher agreement between methods. Erector spinae (ES), on the other hand, showed a very low agreement, that might be related to postural activity before the swing. External oblique (EO) is the first being activated, at 1295 ms prior impact. There is a similar activation time between right and left muscles sides, although the right EO showed better agreement between methods than left side. Therefore, the algorithms usage is task- and muscle-dependent. 相似文献
955.
Ferrette Bruno Lopes da Silva Mourato Bruno Hazin Fábio Hissa Vieira Arocha Freddy Williams Samuel Mackey Rodrigues Junior Carlos Egberto Porto-Foresti Fábio de Amorim Alberto Ferreira Rotundo Matheus Marcos Coelho Rui Hoolihan John P. Sow Fambaye Ngom Diaha N’guessan Constance Romanov Evgeny V. Domingues Rodrigo Rodrigues Oliveira Claudio Foresti Fausto Mendonça Fernando Fernandes 《Hydrobiologia》2021,848(17):3883-3904
Hydrobiologia - Since the Miocene profound climatic changes have influenced the biology and ecology of species worldwide, such as their connectivity, genetic population structure, and biogeography.... 相似文献
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Brêda-Alves Fernanda de Oliveira Fernandes Valéria Chia Mathias Ahii 《Aquatic Ecology》2021,55(2):347-361
Aquatic Ecology - Agrochemicals such as herbicides change the physical and chemical conditions of aquatic ecosystems and alter the community structure and dynamics of phytoplankton. Cyanobacteria... 相似文献
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