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81.
Herrera-Vigenor F Hernández-García R Valadez-Sánchez M Vázquez-Prado J Reyes-Cruz G 《Biochemical and biophysical research communications》2006,347(4):924-930
Calcium-sensing receptor (CaR) activates intracellular pathways controlling calcium homeostasis. CaR carboxyl-terminal mutants associated with metabolic diseases suggest that unidentified proteins interact with the carboxyl-terminal region of this receptor. To address this possibility, we screened for CaR-interacting proteins using the carboxyl terminus of CaR (CaRDelta895-1075 deletion mutant). We identified AMSH, an ubiquitin isopeptidase, as a CaR-interacting partner. AMSH caused a decrease on the signaling properties of wild-type and mutant CaR. Our results indicate that AMSH, which has been recently characterized as a regulator of the endosomal sorting of epidermal growth factor receptor, represents a novel modulator of CaR signaling. 相似文献
82.
Martínez MG Prado Acosta M Candurra NA Ruzal SM 《Biochemical and biophysical research communications》2012,426(4):590-595
We investigated the regulation of Hsp27 phosphorylation by protein kinase C δ (PKCδ) during etoposide-induced apoptosis. The phosphorylation of Hsp27 at Ser78 was temporally correlated with the proteolytic activation of PKCδ during apoptosis. Hsp27 phosphorylation was dependent on the activity of PKCδ since treatment with rottlerin, a chemical inhibitor of PKCδ, or overexpression of a PKCδ dominant negative mutant abolished the phosphorylation. In addition, recombinant PKCδ phosphorylated Hsp27 at Ser78 in vitro. Moreover, caspase-3 was specifically activated following Hsp27 phosphorylation at Ser78. Pull-down assays using a phosphomimetic Hsp27 mutant revealed that binding between Hsp27 and cytochrome c was abolished by the phosphorylation. These results suggest that Hsp27 dissociates from cytochrome c following PKCδ-mediated phosphorylation at Ser78, which allows formation of the apoptosome and stimulates apoptotic progression. 相似文献
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Carlos Roberto Maximiano da Silva Leandro Bento da Silva Célia Guadalupe Tardelli de Jesus Andrade Rafael Trevisan María Socorro González-Elizondo André Luís Laforga Vanzela 《Plant Systematics and Evolution》2012,298(2):391-398
Micromorphology of the achene surface of 26 Brazilian species of Eleocharis was studied by scanning electron microscopy in order to evaluate its usefulness in the taxonomy of the genus. The results
point out two patterns of cell organization according to silica structures of achenes. The first corresponds to a group of
species (group A) that have small to medium cells arranged vertically. The second is found in those species (group B) with
medium to large cells arranged horizontally. These data were useful in separating species of Eleocharis subgenus Scirpidium and E. subgenus Limnochloa (group B) from E. subgenus Eleocharis (group A). However, group A shows considerable variation in silica wall arrangement. Eleocharis
squamigera, previously considered as part of E. subgenus Eleocharis, shows features rather similar to those of Scirpidium, confirming recent phylogenies. The subgenus Limnochloa was clearly distinguished from others by achenes with large cells (over 55 μm width), presence of crenate or repand anticlinal
walls, and some orifices near the wall in some species. The silica wall ornamentation seems to be a useful morphological tool
for studying relationships between subgenera and distinguishes Limnochloa from the other subgenera. 相似文献
86.
Bacterial resistance to multiple antibiotics is a health problem. Essential oils (EOs) possess antibacterial properties and have been screened as potential sources of novel antimicrobial compounds. Terpenes and terpenoids are components derived from EOs. Some of these EOs show inhibitory activity against Staphylococcus aureus. Carvacrol has specific effects on S. aureus and Staphylococcus epidermidis. Perilla oil suppresses expression of α-toxin, Staphylococcus enterotoxin A and B and toxic shock syndrome toxin. Geraniol shows good activity in modulating drug resistance in several gram-negative species. EOs could act as biopreservatives, reducing or eliminating pathogenic bacteria and increasing the overall quality of animal and vegetable food products. Although clinical studies are scarce, the uses of EOs for topical administration and as penetration enhancers for antiseptics are promising. Little information exists for oral administration. 相似文献
87.
? Although a major expectation of coevolutionary theory between plants and herbivores is the occurrence of reciprocal local adaptation, this has remained almost untested. Thus, we evaluated the presence and variation in the patterns of reciprocal local adaptation between an herbivorous insect and its host plant. ? Two four-by-four cross-infestation experiments were performed under similar abiotic conditions. The first one was done under laboratory conditions to estimate herbivore individual performance while the second one was performed in a common garden to simultaneously estimate herbivore population growth rate as well as seed production and plant defenses (resistance and tolerance to herbivory). ? The patterns of population differentiation for the herbivore and the plant were not independent of each other, showing all the possible outcomes from locally adapted to maladapted populations. These results indicate differences in the magnitude of local adaptation. While an association between resistance and herbivore performance was observed, there was no clear pattern between tolerance and herbivore local adaptation. ? Our results demonstrated the occurrence of reciprocal local adaptation following the pattern expected by theory: when the herbivores or the plants were adapted, the other species was non-adapted or even maladapted. 相似文献
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RS Mehta A Rodriguez M Chico I Guadalupe N Broncano C Sandoval F Tupiza E Mitre PJ Cooper 《PLoS neglected tropical diseases》2012,6(7):e1753
Background
Children of mothers infected with soil-transmitted helminths (STH) may have an increased susceptibility to STH infection.Methods and Findings
We did a case-control study nested in a birth cohort in Ecuador. Data from 1,004 children aged 7 months to 3 years were analyzed. Cases were defined as children with Ascaris lumbricoides and/or Trichuris trichiura, controls without. Exposure was defined as maternal infection with A. lumbricoides and/or T. trichiura, detected during the third trimester of pregnancy. The analysis was restricted to households with a documented infection to control for infection risk. Children of mothers with STH infections had a greater risk of infection compared to children of uninfected mothers (adjusted OR 2.61, 95% CI: 1.88–3.63, p<0.001). This effect was particularly strong in children of mothers with both STH infections (adjusted OR: 5.91, 95% CI: 3.55–9.81, p<0.001). Newborns of infected mothers had greater levels of plasma IL-10 than those of uninfected mothers (p = 0.033), and there was evidence that cord blood IL-10 was increased among newborns who became infected later in childhood (p = 0.060).Conclusion
Our data suggest that maternal STH infections increase susceptibility to infection during early childhood, an effect that was associated with elevated IL-10 in cord plasma. 相似文献90.