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1.
R. E. McFadyen 《BioControl》1979,24(3):281-287
The mealybugHypogeococcus festerianus (Lizer y Trelles) infests cacti in Northern Argentina and Paraguay, causing deformed and distorted growth of attacked plants. Laboratory studies
and field observations demonstrate that it will only infest plants in the sub-familyCereanae of theCactaceae. Its liberation in Queensland, Australia, for the control ofEriocereus spp., was approved in October 1974, and it has since established widely.
Résumé La cochenille farineuseHypogeococcus festerianus (Lizer y Trelles) infeste les cactus dans le nord de l’Argentine et le Paraguay, causant chez ces plantes, des déformations et une croissance anormale. Les observations faites dans la nature et en laboratoire montrent qu’elle s’attaque exclusivement aux plantes de la sous-famille desCereanae de la famille desCactaceae. Son introduction en Australie a été approuvée en octobre 1974, et elle s’est largement établie depuis.相似文献
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The binding of platinum (II)-terpyridine complexes to DNA was studied by using equilibrium dialysis. Optical absorption methods were used to measure the ability of the ligands to aggregate in aqueous buffer. Scatchard plots for the binding of the monomeric [Pt(terpy)SC4H9]+ cation to DNA at I0.01 are curvilinear, concave upwards, suggesting two modes of binding. The association constant decreases at higher ionic strengths, consistent with polyelectrolyte theory, and 1.1 cations are released per bound ligand molecule. The association constants of the binuclear ligands [Pt(terpy)S[CH2]4S(terpy)Pt]2+ and [Pt(terpy)S[CH2]6S(terpy)Pt]2+ are 8 and 23 times larger respectively than the affinity of the monomer. For the latter binuclear derivative the increase may be ascribed to bifunctional reaction. Differential dialysis experiments with DNAs of differing base composition show that [Pt(terpy)SC4H9]+ has a requirement for a single G X C base-pair at the highest-affinity site. However, in the binuclear ligands chromophore specificity is severely compromised. Similar experiments indicate that 9-aminoacridine and selected methylene-linked diacridines show no significant sequence selectivity. 相似文献
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Sara Santarossa Alexandra R. Sitarik Christine Cole Johnson Jia Li Susan V. Lynch Dennis R. Ownby Alex Ramirez Germaine LM. Yong Andrea E. Cassidy-Bushrow 《Journal of Exercise Nutrition & Biochemistry》2021,25(4):24
[Purpose] To determine whether physical activity (PA), primarily the recommended 60 minutes of moderate-to-vigorous PA, is associated with gut bacterial microbiota in 10-year-old children.[Methods] The Block Physical Activity Screener, which provides minutes/day PA variables, was used to determine whether the child met the PA recommendations. 16S rRNA sequencing was performed on stool samples from the children to profile the composition of their gut bacterial microbiota. Differences in alpha diversity metrics (richness, Pielou’s evenness, and Faith’s phylogenetic diversity) by PA were determined using linear regression, whereas beta diversity (unweighted and weighted UniFrac) relationships were assessed using PERMANOVA. Taxon relative abundance differentials were determined using DESeq2.[Results] The analytic sample included 321 children with both PA and 16S rRNA sequencing data (mean age [SD] =10.2 [0.8] years; 54.2% male; 62.9% African American), where 189 (58.9%) met the PA recommendations. After adjusting for covariates, meeting the PA recommendations as well as minutes/day PA variables were not significantly associated with gut richness, evenness, or diversity (p ≥ 0.19). However, meeting the PA recommendations (weighted UniFrac R2 = 0.014, p = 0.001) was significantly associated with distinct gut bacterial composition. These compositional differences were partly characterized by increased abundance of Megamonas and Anaerovorax as well as specific Christensenellaceae_R-7_group taxa in children with higher PA.[Conclusion] Children who met the recommendations of PA had altered gut microbiota compositions. Whether this translates to a reduced risk of obesity or associated metabolic diseases is still unclear. 相似文献
6.
Distinct intracellular signaling mediates C‐MET regulation of dendritic growth and synaptogenesis 下载免费PDF全文
Kathie L. Eagleson Christianne J. Lane Lisa McFadyen‐Ketchum Sara Solak Hsiao‐Huei Wu Pat Levitt 《Developmental neurobiology》2016,76(10):1160-1181
Hepatocyte growth factor (HGF) activation of the MET receptor tyrosine kinase influences multiple neurodevelopmental processes. Evidence from human imaging and mouse models shows that, in the forebrain, disruptions in MET signaling alter circuit formation and function. One likely means of modulation is by controlling neuron maturation. Here, we examined the signaling mechanisms through which MET exerts developmental effects in the neocortex. In situ hybridization revealed that hgf is located near MET‐expressing neurons, including deep neocortical layers and periventricular zones. Western blot analyses of neocortical crude membranes demonstrated that HGF‐induced MET autophosphorylation peaks during synaptogenesis, with a striking reduction in activation between P14 and P17 just before pruning. In vitro analysis of postnatal neocortical neurons assessed the roles of intracellular signaling following MET activation. There is rapid, HGF‐induced phosphorylation of MET, ERK1/2, and Akt that is accompanied by two major morphological changes: increases in total dendritic growth and synapse density. Selective inhibition of each signaling pathway altered only one of the two distinct events. MAPK/ERK pathway inhibition significantly reduced the HGF‐induced increase in dendritic length, but had no effect on synapse density. In contrast, inhibition of the PI3K/Akt pathway reduced HGF‐induced increases in synapse density, with no effect on dendritic length. The data reveal a key role for MET activation during the period of neocortical neuron growth and synaptogenesis, with distinct biological outcomes mediated via discrete MET‐linked intracellular signaling pathways in the same neurons. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 76: 1160–1181, 2016 相似文献
7.
Recruitment of TBK1 to cytosol‐invading Salmonella induces WIPI2‐dependent antibacterial autophagy 下载免费PDF全文
Teresa LM Thurston Keith B Boyle Mark Allen Benjamin J Ravenhill Maryia Karpiyevich Stuart Bloor Annie Kaul Jessica Noad Agnes Foeglein Sophie A Matthews David Komander Mark Bycroft Felix Randow 《The EMBO journal》2016,35(16):1779-1792
Mammalian cells deploy autophagy to defend their cytosol against bacterial invaders. Anti‐bacterial autophagy relies on the core autophagy machinery, cargo receptors, and “eat‐me” signals such as galectin‐8 and ubiquitin that label bacteria as autophagy cargo. Anti‐bacterial autophagy also requires the kinase TBK1, whose role in autophagy has remained enigmatic. Here we show that recruitment of WIPI2, itself essential for anti‐bacterial autophagy, is dependent on the localization of catalytically active TBK1 to the vicinity of cytosolic bacteria. Experimental manipulation of TBK1 recruitment revealed that engagement of TBK1 with any of a variety of Salmonella‐associated “eat‐me” signals, including host‐derived glycans and K48‐ and K63‐linked ubiquitin chains, suffices to restrict bacterial proliferation. Promiscuity in recruiting TBK1 via independent signals may buffer TBK1 functionality from potential bacterial antagonism and thus be of evolutionary advantage to the host. 相似文献
8.
Catalano JG Deaton DN Furfine ES Hassell AM McFadyen RB Miller AB Miller LR Shewchuk LM Willard DH Wright LL 《Bioorganic & medicinal chemistry letters》2004,14(1):275-278
The synthesis and biological activity of a series of aldehyde inhibitors of cathepsin K are reported. Exploration of the properties of the S(1) subsite with a series of alpha-amino aldehyde derivatives substituted at the P(1) position afforded compounds with cathepsin K IC(50)s between 52 microM and 15 nM. 相似文献
9.
New perspectives of locomotor rehabilitation after stroke 总被引:1,自引:0,他引:1
The task-oriented approach incorporating treadmill walking for retraining gait early after stroke has contributed to promote locomotor recovery. To augment practice, training strategies such as mental practice and training in virtual environments are proposed. While the former offers more practice with less physical exertion, the latter allows safe practice in a variety of challenging environments. Work is under way to assess whether these new strategies can further enhance locomotor recovery. 相似文献
10.
Michael Carland Murray J. Cairns Vanessa J. Roknic W. David McFadyen 《Journal of inorganic biochemistry》2010,104(8):815-819
Three platinum complexes in which substituted (7-OMe, 9-NH2; 7-F, 9-NH2; and 7-H, 9-NH(CH2)2OH) 9-aminoacridine-4-carboxamides were tethered to a platinum(II)diamine moiety were synthesised and characterised at the chemical and biological level. These variants showed a decrease in cytotoxicity, as measured by IC50 values in HeLa cells, when compared with the parent 7-H, 9-NH2 compound. The 7-F and 9-NH(CH2)2OH substituents gave rise to a small decrease in cytotoxicity, and the 7-OMe substituent resulted in a larger decrease in cytotoxicity. Their binding to purified pUC19 plasmid DNA was investigated and it was found that the addition of 7-F, 9-NH(CH2)2OH and especially the 7-OMe substituents, resulted in reduced DNA binding. This correlated well with the IC50 cytotoxicity values. However, the DNA sequence selectivity was unaffected by the addition of these moieties. 相似文献