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171.
Ilaria Saltarella Aurelia Lamanuzzi Antonia Reale Angelo Vacca Roberto Ria 《World journal of stem cells》2015,7(1):84-95
Multiple myeloma (MM) is a hematologic malignancy of monoclonal plasma cells which remains incurable despite recent advances in therapies. The presence of cancer stem cells (CSCs) has been demonstrated in many solid and hematologic tumors, so the idea of CSCs has been proposed for MM, even if MM CSCs have not been define yet. The existence of myeloma CSCs with clonotypic B and clonotypic non B cells was postulated by many groups. This review aims to focus on these distinct clonotypic subpopulations and on their ability to develop and sustain MM. The bone marrow microenvironment provides to MM CSCs self-renewal, survival and drug resistance thanks to the presence of normal and cancer stem cell niches. The niches and CSCs interact each other through adhesion molecules and the interplay between ligands and receptors activates stemness signaling (Hedgehog, Wnt and Notch pathways). MM CSCs are also supposed to be responsible for drug resistance that happens in three steps from the initial cancer cell homing microenvironment-mediated to development of microenvironment-independent drug resistance. In this review, we will underline all these aspects of MM CSCs. 相似文献
172.
Influence of selected carbohydrates on rhizogenesis of shoots saucer magnolia in vitro 总被引:1,自引:0,他引:1
Aurelia Kamenicka 《Acta Physiologiae Plantarum》1998,20(4):425-429
Nodal segements were taken from juvenile shoots of mature 100 year-old trees of saucer magnolia (Magnolia x soulangiana Soul.-Bod.) and cultured on Standardi and Catalano medium supplemented with 1.33 μmol·dm−3 BA, 0.54 μmol·dm−3 NAA, 58 μmol·dm−3 sucrose and 6.0 g·l−1 agar-agar. After 8 weeks, separated shoots were transferred to rooting medium with half-strength macronutrients (basal medium)
supplemented with 0.3% activated charcoal and one of carbohydrates: arabinose, cellulose, fructose, galactose, glucose, lactose,
mannose, rhamnose, ribose, sorbose, sucrose or xylose at 20 g·dm−3 and 7.0 g·dm−3 agar-agar. After 13 weeks of culture, shoot number, fresh and dry weight of shoots and roots, total root length and number
of roots/per shoot were recorded. Percentages of rooted shoots were calculated. Fructose, mannose and xylose were the most
effective carbon source on shoot proliferation followed by sucrose. The rooting response was induced by cellulose and xylose.
Arabinose, rhamnose and sorbose inhibited root formation. The number of adventitious roots produced per shoot was stimulated
by cellulose and xylose. Total biomass (shoot plus roots) of the plantlets was the highest at fructose and cellulose. 相似文献
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Rivers are among the most endangered ecosystems of the world with dramatically decreasing biodiversity. Rehabilitation programmes
aiming at restoration of riverine ecosystems rely on the recolonisation of native macroinvertebrates from refuges. We examined
whether a relatively natural remnant of the former river Rhine (Altrhein) harbours a higher richness of benthic macroinvertebrates
than two sites of the modified Rhine with artificial and semi-natural embankments near Basel. All three sites were bimonthly
sampled between May 2007 and May 2008 using three techniques: Kick and Sweep, drifting animals collected from pieces of stone
turned by hand, and animals collected from stone surfaces. Taxa richness was higher in the Altrhein than in the two sampling
sites in the river Rhine, but it was mainly a result of the large number of individuals sampled at this site. Despite 17%
of taxa recorded were alien, the three sampling sites differed neither in the number of alien taxa nor in their abundances.
However, lower percentages of both alien taxa and individuals were recorded in the Altrhein than at the other two sites in
the Rhine. Indicator value analysis showed that the macroinvertebrate community of the Altrhein maintains several native and
specific taxa. Multivariate analyses supported the separation of the communities collected at different sampling sites and
also the uniqueness of the community in the Altrhein. The observed patterns, however, strongly depended on the sampling method
applied, thereby calling the attention to the application of standard sampling methods and also to the restriction of result
comparisons on projects using identical sampling methodology. Our study shows that the remnant of the former river Rhine serves
as a refuge for macroinvertebrates which may facilitate future restoration of the river embankment. 相似文献
175.
K. Aurelia Ball Jeffrey R. Johnson Mary K. Lewinski John Guatelli Erik Verschueren Nevan J. Krogan Matthew P. Jacobson 《PLoS computational biology》2016,12(6)
Growing evidence supports other regulatory roles for protein ubiquitination in addition to serving as a tag for proteasomal degradation. In contrast to other common post-translational modifications, such as phosphorylation, little is known about how non-degradative ubiquitination modulates protein structure, dynamics, and function. Due to the wealth of knowledge concerning protein kinase structure and regulation, we examined kinase ubiquitination using ubiquitin remnant immunoaffinity enrichment and quantitative mass spectrometry to identify ubiquitinated kinases and the sites of ubiquitination in Jurkat and HEK293 cells. We find that, unlike phosphorylation, ubiquitination most commonly occurs in structured domains, and on the kinase domain, ubiquitination is concentrated in regions known to be important for regulating activity. We hypothesized that ubiquitination, like other post-translational modifications, may alter the conformational equilibrium of the modified protein. We chose one human kinase, ZAP-70, to simulate using molecular dynamics with and without a monoubiquitin modification. In Jurkat cells, ZAP-70 is ubiquitinated at several sites that are not sensitive to proteasome inhibition and thus may have other regulatory roles. Our simulations show that ubiquitination influences the conformational ensemble of ZAP-70 in a site-dependent manner. When monoubiquitinated at K377, near the C-helix, the active conformation of the ZAP-70 C-helix is disrupted. In contrast, when monoubiquitinated at K476, near the kinase hinge region, an active-like ZAP-70 C-helix conformation is stabilized. These results lead to testable hypotheses that ubiquitination directly modulates kinase activity, and that ubiquitination is likely to alter structure, dynamics, and function in other protein classes as well. 相似文献
176.
Joanna Pastwińska Aurelia Walczak-Drzewiecka Magdalena Łukasiak Marcin Ratajewski 《Cell Adhesion & Migration》2020,14(1):106-117
ABSTRACTA decrease in oxygen concentration is a hallmark of inflammatory reactions resulting from infection or homeostasis disorders. Mast cells interact with extracellular matrix and other cells by adhesion receptors. We investigated the effect of hypoxia on integrin-mediated mast cell adhesion to fibronectin. We found that it was mediated by the α5/β1 receptor and that hypoxia significantly upregulated this process. Hypoxia-mediated increases in mast cell adhesion occurred without increased surface expression of integrins, suggesting regulation by inside-out integrin signaling. Hypoxia also mediated an increase in phosphorylation of Akt, and PI3’kinase inhibitors abolished hypoxia-mediated mast cell adhesion. Hypoxia upregulates the function of integrin receptors by PI3’ kinase-dependent signaling. This process might be important for the location of mast cells at inflammatory sites 相似文献
177.
The effect of different concentrations and activities of cytokinins on the morphogenesis of regenerated Rhododendron forrestii Balf. f. ex Diels. shoots taken from nodal segments were tested. We evaluated zeatin, zeatin riboside, izopentyladenine,
izopentyladenine riboside, kinetin, kinetin riboside, benzylaminopurine, benzylaminopurine riboside. The experimental results
were evaluated by mathematical methods and regression analysis describing the effect of isoprenic and aromatic type of cytokinins.
On the basis of this modelling, maximum axillary shoot production was attained with medium supplemented with 2.0 mg·l−1 izopentyladenine riboside, 2.0 mg·l−1 benzylaminopurine and 20 g·l−1 sucrose. Minimal axillary shoots were produced with kinetin and kinetin riboside. 相似文献
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