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111.
Leandro Da Silva Duarte Rodrigo Scarton Bergamin Vinícius Marcilio-Silva Guilherme Dubal Dos Santos Seger Márcia Cristina Mendes Marques 《PloS one》2014,9(8)
Phylobetadiversity is defined as the phylogenetic resemblance between communities or biomes. Analyzing phylobetadiversity patterns among different vegetation physiognomies within a single biome is crucial to understand the historical affinities between them. Based on the widely accepted idea that different forest physiognomies within the Southern Brazilian Atlantic Forest constitute different facies of a single biome, we hypothesize that more recent phylogenetic nodes should drive phylobetadiversity gradients between the different forest types within the Atlantic Forest, as the phylogenetic divergence among those forest types is biogeographically recent. We compiled information from 206 checklists describing the occurrence of shrub/tree species across three different forest physiognomies within the Southern Brazilian Atlantic Forest (Dense, Mixed and Seasonal forests). We analyzed intra-site phylogenetic structure (phylogenetic diversity, net relatedness index and nearest taxon index) and phylobetadiversity between plots located at different forest types, using five different methods differing in sensitivity to either basal or terminal nodes (phylogenetic fuzzy weighting, COMDIST, COMDISTNT, UniFrac and Rao’s H). Mixed forests showed higher phylogenetic diversity and overdispersion than the other forest types. Furthermore, all forest types differed from each other in relation phylobetadiversity patterns, particularly when phylobetadiversity methods more sensitive to terminal nodes were employed. Mixed forests tended to show higher phylogenetic differentiation to Dense and Seasonal forests than these latter from each other. The higher phylogenetic diversity and phylobetadiversity levels found in Mixed forests when compared to the others likely result from the biogeographical origin of several taxa occurring in these forests. On one hand, Mixed forests shelter several temperate taxa, like the conifers Araucaria and Podocarpus. On the other hand, tropical groups, like Myrtaceae, are also very representative of this forest type. We point out to the need of more attention to Mixed forests as a conservation target within the Brazilian Atlantic Forest given their high phylogenetic uniqueness. 相似文献
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Thaís C. Lima Rodrigo Lucarini Angelica C. Volpe Carolina Q.J. de Andrade Alice M.P. Souza Patricia M. Pauletti Ana H. Januário Guilherme V. Símaro Jairo K. Bastos Wilson R. Cunha Alexandre Borges Rosangela da Silva Laurentiz Valéria A. Conforti Renato L.T. Parreira Carly H.G. Borges Giovanni F. Caramori Karla F. Andriani Márcio L.A. e Silva 《Bioorganic & medicinal chemistry letters》2017,27(2):176-179
(?)-Cubebin (CUB), isolated from seeds of Piper cubeba, was used as starting material to obtain the derivatives (?)-hinokinin (HK) and (?)-O-benzyl cubebin (OBZ). Using paw edema as the experimental model and different chemical mediators (prostaglandin and dextran), it was observed that both derivatives were active in comparison with both negative (5% Tween® 80 in saline) and positive (indomethacin) controls. The highest reduction in the prostaglandin-induced edema was achieved by OBZ (66.0%), while HK caused a 59.2% reduction. Nonetheless, the dextran-induced paw edema was not significantly reduced by either of the derivatives (HK or OBZ), which inhibited edema formation by 18.3% and 3.5%, respectively, in contrast with the positive control, cyproheptadine, which reduced the edema by 56.0%. The docking analysis showed that OBZ presented the most stable ligand-receptor (COX-2 – cyclooxygenase-2) interaction in comparison with CUB and HK. 相似文献
114.
Xanthomonas campestris attenuates virulence by sensing light through a bacteriophytochrome photoreceptor 下载免费PDF全文
115.
The biomethane potential and biodegradability of an array of substrates with highly heterogeneous characteristics, including mono- and co-digestion samples with dairy manure, was determined using the biochemical methane potential (BMP) assay. In addition, the ability of two theoretical methods to estimate the biomethane potential of substrates and the influence of biodegradability was evaluated. The results of about 175 individual BMP assays indicate that substrates rich in lipids and easily-degradable carbohydrates yield the highest methane potential, while more recalcitrant substrates with a high lignocellulosic fraction have the lowest. Co-digestion of dairy manure with easily-degradable substrates increases the specific methane yields when compared to manure-only digestion. Additionally, biomethane potential of some co-digestion mixtures suggested synergistic activity. Evaluated theoretical methods consistently over-estimated experimentally-obtained methane yields when substrate biodegradability was not accounted. Upon correcting the results of theoretical methods with observed biodegradability data, an agreement greater than 90% was achieved. 相似文献
116.
Fernández-Real JM Moreno-Navarrete JM Ortega F Ricart W 《Obesity (Silver Spring, Md.)》2011,19(7):1511-1514
Decreased serum creatinine concentration has been recently described to constitute a new risk factor of type 2 diabetes. Increased free radicals have been consistently associated with decreased serum creatinine and with cellular senescence. Telomere length is considered as a biological marker for senescence. We aimed to study the association of telomere length with serum creatinine. Telomere length of subcutaneous adipose tissue cells was measured in a sample of obese and nonobese subjects (n = 49). Telomere length of subcutaneous adipose tissue cells was positively associated with serum creatinine (r = 0.40, P = 0.004), i.e., the lower the telomere length, the lower the serum creatinine, but not with glomerular filtration rate (GFR). In addition, telomere length was negatively associated with BMI (r = -0.45, P = 0.001) and systolic blood pressure (r = -0.41, P = 0.003). In a multiple linear regression analysis, BMI (P = 0.005), systolic blood pressure (P = 0.01) and telomere length (P = 0.03) independently contributed to 37% of serum creatinine variance after controlling for sex and age. In conclusion, the association of serum creatinine with a marker of cellular senescence suggests an underlying mechanism influencing both decreased serum creatinine and increased risk of type 2 diabetes. 相似文献
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M Sanchez-Moreno J E Ortega A Sanchez-Navas J M Salas-Peregrin M Monteoliva 《International journal for parasitology》1989,19(7):743-748
Copper-zinc, cyanide-sensitive superoxide dismutase (Cu-Zn-SOD) was detected in homogenates of Moniezia expansa. The enzyme was purified by a sequence of multiple differential centrifugations, ammonium sulphate precipitation, ion-exchange and G-75 Sephadex column chromatography. The final enzyme preparation had a specific activity of 623.00 +/- 9.97U per mg protein and, after isolation, a single-staining band on acrylamide-SDS gels was detected which coincided with enzyme activity. The inhibitory activities of several benzimidazoles and several novel pyrimidine derivatives were determined on purified extracts of the M. expansa Cu-Zn-SOD. The results indicated that the percentage inhibition of Cu-Zn-SOD by some pyrimidine derivatives (6-amino-1, 3-dimethyl-5-nitroso-uracil, 6-amino-5-methyl-5-nitroso-uracil and 5-amino-uracil) was markedly higher than inhibition with the benzimidazoles. 相似文献
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Reduced dopamine and glutamate neurotransmission in the nucleus accumbens of quinpirole‐sensitized rats hints at inhibitory D2 autoreceptor function 下载免费PDF全文