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41.
42.
Gortazar C Torres MJ Acevedo P Aznar J Negro JJ de la Fuente J Vicente J 《BMC microbiology》2011,11(1):27
Background
We describe the diversity of two kinds of mycobacteria isolates, environmental mycobacteria and Mycobacterium bovis collected from wild boar, fallow deer, red deer and cattle in Do?ana National Park (DNP, Spain), analyzing their association with temporal, spatial and environmental factors. 相似文献43.
Monica Martinez-Haro Andy J. Green Pelayo Acevedo Rafael Mateo 《European Journal of Wildlife Research》2011,57(3):475-484
The ingestion of spent Pb shot due to confusion with grit or inadvertently with food particles causes Pb poisoning in a large
number of waterbirds, this being one of the main causes of mortality for some species. Lead ammunition for hunting is being
progressively banned in more countries, while grit supplementation has been proposed as a management measure to reduce the
ingestion of deposited Pb shot. Studies of grit selection with waterfowl in semi-captivity and in the wild were undertaken
to evaluate preferences in the colour and geochemical composition of grit, whether it was available dry or in water, its position
within the wetland and the relationship between grit ingestion and feeding behaviour. Grit ingestion was higher when food
was included in the treatments. In the absence of food, red grit was taken in higher amounts than grey in semi-captivity but
not in the wild. Siliceous grit was taken in a higher amount than calcareous when offered dry, but not in water. No differences
in the amount of ingested grit were found among different positions within the wetland. The number of feeding attempts in
plots supplemented with grit was higher than in those without grit, although the highest numbers of feeding birds were found
in plots supplemented with food. Grit ingestion in waterfowl is intimately associated with feeding behaviour. To optimize
the effectiveness of grit supplementation to reduce the risk of Pb poisoning in waterfowl, calcareous and siliceous grit may
be combined and applied in feeding sites or mixed with bait to attract birds. 相似文献
44.
Weber D Gorzalczany S Martino V Acevedo C Sterner O Anke T 《Zeitschrift für Naturforschung. C, Journal of biosciences》2005,60(5-6):467-477
Erythrina crista-galli (Fabaceae) is used in Argentinean ethnopharmacology as anti-inflammatory medication, narcotic, desinfectant, and for the treatment of wounds. The common name of the tree is "ceibo" or coral tree. The dominating endophytes in E. crista-galli all belong to the genus Phomopsis as identified by microscopic features and the analysis of their ITS sequences. To investigate a possible contribution of Phomopsis spp. to the metabolites found in the plant, twelve different isolates were cultivated in different media. Besides several new metabolites a number of known compounds were detected: mellein, nectriapyrone, 4-hydroxymellein, scytalone, tyrosol, clavatol, mevinic acid, and mevalonolactone. 相似文献
45.
Badyaev AV Acevedo Seaman D Navara KJ Hill GE Mendonça MT 《Journal of evolutionary biology》2006,19(4):1044-1057
Overlap in growth of offspring should constrain the opportunity for sex-biased maternal effects, yet sex-specific allocation of maternal resources among simultaneously growing ova is often observed in vertebrates. In birds, such allocation can be accomplished either by temporal clustering of ova that become the same sex, resulting in sex-biased egg-laying order, or by follicle-specific delivery of maternal resources. Two house finch populations at the northern and southern boundaries of the species range have opposite ovulation sequences of male and female eggs, and thus, in the absence of sex differences in ova growth or sex-specific maternal strategies, would be expected to have opposite sex-specific accumulation of maternal products. We found that the populations had strong and similar gradients of steroid distribution in relation to ovulation order, whereas distribution of carotenoids and vitamins correlated with each follicle's accumulation of steroids. In both populations, temporal bias in production of sons and daughters within a clutch enabled strongly sex-specific acquisition of maternal products, and oocytes of the same sex were highly interdependent in their accumulation of steroids. Moreover, in nests where the sex-bias in relation to ovulation order deviated from population-specific patterns, eggs had highly distinct concentrations of steroids, carotenoids and vitamins. These results and previous findings of sex-specific yolk partitioning among oocytes suggest that oocytes that become males and females are temporally or spatially clustered during their ovarian growth. We discuss the implication of these findings for the evolution of sex-specific maternal resource allocation. 相似文献
46.
Intracellular Ca2+ regulates many fundamental physiological processes in excitable and non-excitable cells. Certainly this is the case of sperm where the local concentration of intracellular Ca2+ ([Ca2+]i) is significantly influenced by Ca2+ permeable channels present in the cell plasma membrane. Amongst these channels, the voltage dependent Ca2+ channels (CaV) of the T-type (CaV3) appear to have an eminent role in the acrosome reaction (AR) of some sperm species, though they may participate in other important functions like motility and capacitation. The AR is an exocytotic event where the acrosome vesicle in the posterior region of the head fuses with the plasma membrane. This reaction allows sperm to fuse and fertilize the egg. Here we summarize our present knowledge regarding CaV3 channels in sperm, show the first direct electrophysiological evidence for their presence in maturing mouse sperm and discuss some of the relevant unanswered questions. 相似文献
47.
48.
Michela Palmieri Maria Almeida Intawat Nookaew Horacio GomezAcevedo Teenamol E. Joseph Xuchu Que Sotirios Tsimikas Xiaoli Sun Stavros C. Manolagas Joseph L. Witztum Elena Ambrogini 《Aging cell》2021,20(8)
Oxidized phospholipids (OxPLs) are pro‐inflammatory molecules that affect bone remodeling under physiological conditions. Transgenic expression of a single‐chain variable fragment (scFv) of the antigen‐binding domain of E06, an IgM natural antibody that recognizes the phosphocholine (PC) moiety of OxPLs, increases trabecular and cortical bone in adult male and female mice by increasing bone formation. OxPLs increase with age, while natural antibodies decrease. Age‐related bone loss is associated with increased oxidative stress and lipid peroxidation and is characterized by a decline in osteoblast number and bone formation, raising the possibility that increased OxPLs, together with the decline of natural antibodies, contribute to age‐related bone loss. We show here that transgenic expression of E06‐scFv attenuated the age‐associated loss of spinal, femoral, and total bone mineral density in both female and male mice aged up to 22 and 24 months, respectively. E06‐scFv attenuated the age‐associated decline in trabecular bone, but not cortical bone, and this effect was associated with an increase in osteoblasts and a decrease in osteoclasts. Furthermore, RNA‐seq analysis showed that E06‐scFv increased Wnt10b expression in vertebral bone in aged mice, indicating that blocking OxPLs increases Wnt signaling. Unlike age‐related bone loss, E06‐scFv did not attenuate the bone loss caused by estrogen deficiency or unloading in adult mice. These results demonstrate that OxPLs contribute to age‐associated bone loss. Neutralization of OxPLs, therefore, is a promising therapeutic target for senile osteoporosis, as well as atherosclerosis and non‐alcoholic steatohepatitis (NASH), two other conditions shown to be attenuated by E06‐scFv in mice. 相似文献
49.
VEGF-induced vascular permeability is mediated by FAK 总被引:1,自引:0,他引:1
Chen XL Nam JO Jean C Lawson C Walsh CT Goka E Lim ST Tomar A Tancioni I Uryu S Guan JL Acevedo LM Weis SM Cheresh DA Schlaepfer DD 《Developmental cell》2012,22(1):146-157
Endothelial cells (ECs) form cell-cell adhesive junctional structures maintaining vascular integrity. This barrier is dynamically regulated by vascular endothelial growth factor (VEGF) receptor signaling. We created an inducible knockin mouse model to study the contribution of the integrin-associated focal adhesion tyrosine kinase (FAK) signaling on vascular function. Here we show that genetic or pharmacological FAK inhibition in ECs prevents VEGF-stimulated permeability downstream of VEGF receptor or Src tyrosine kinase activation in vivo. VEGF promotes tension-independent FAK activation, rapid FAK localization to cell-cell junctions, binding of the FAK FERM domain to the vascular endothelial cadherin (VE-cadherin) cytoplasmic tail, and direct FAK phosphorylation of β-catenin at tyrosine-142 (Y142) facilitating VE-cadherin-β-catenin dissociation and EC junctional breakdown. Kinase inhibited FAK is in a closed conformation that prevents VE-cadherin association and limits VEGF-stimulated β-catenin Y142 phosphorylation. Our studies establish a role for FAK as an essential signaling switch within ECs regulating adherens junction dynamics. 相似文献
50.
Genetic and environmental heterogeneity of residual variance of weight traits in Nellore beef cattle