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311.
Guadalupe de la Rosa Hiram Castillo-Michel Gustavo Cruz-Jiménez Jesús Bernal-Alvarado Teodoro Córdova-Fraga Laura López-Moreno 《International journal of phytoremediation》2014,16(11):1073-1086
In order to gain knowledge on the potential use of Helianthus annuus L. for the remediation of Cr(VI) polluted waters, hydroponics experiments were set up to determine Cr uptake and tolerance in different Cr(VI)-sulfate conditions, and Cr biotransformations. Results indicated that Cr(VI) promoted seed germination, and plant tolerance was higher at younger plant stages. Cr uptake was dependent on sulfate concentrations. The highest Cr levels in roots and shoots (13,700 and 2,500 mg kg–1dry weight (DW), respectively) were obtained in 1 mM sulfate. The lowest Cr uptake in roots (10,600 mg kg–1DW) was observed in seedlings treated with no sulfate. In shoots, Cr concentration was of 1,500 mg kg–1DW for the 1 mM sulfate treatment, indicating a different level of interaction between chromate and sulfate in both tissues. For the first time, using micro X-ray florescence (μXRF), we demonstrated Cr reaches the root stele and is located in the walls of xylem vessels. Bulk and micro X-ray Absorption Near-Edge Structure (μXANES) results showed that Cr in the roots is mostly in the form of Cr(III) phosphate (80%), with the remainder complexed to organic acids. Our results suggest this plant species may serve for Cr(VI) rhizofiltration purposes. 相似文献
312.
Calycogonium formonense, a new species, is here described from the floristically diverse Massif de la Hotte of southern Haiti. It is compared to
C. hispidulum, to which it is likely related. Although the genus Calycogonium is not monophyletic, C. formonense and C. hispidulum are probably related to other species, e.g., C. calycopteris, C. heterophyllum, and C. reticulatum, that exhibit reduced inflorescences and 4-merous flowers having hypanthia with four conspicuous lobes separated by longitudinal
grooves and external calyx lobes that are flattened parallel to the floral radii. These distinctive species may form a clade.
Calycogonium formonense is distinguished from C. hispidulum by its smaller leaves with the tertiary veins not raised on the abaxial surface, with entire margins (i.e., margin without
elongate multicellular hairs), and usually solitary flowers. 相似文献
313.
314.
Teodoro Perri 《Development genes and evolution》1934,131(1):113-134
Conclusioni Tenendo presenti le conclusioni tratte da ciascun gruppo di queste csperienze di espianto in soluzione diRinger diluita, posso affermare che l'abbozzo (rispettivamente territorio) dell'occhio ha, sia allo stadio di vescicola ottica primaria sia di neurula (docce midollari ampiamente aperte e un poco sollevate), insita in sè stesso la capacità di autodifferenziarsi, di regolarsi, di fondersi con un'altra vescicola ottica (previa asportazione di una parte di ciascun d'esse) e regolarsi, di determinare un cristallino su ectoderma indifferente (inBufo vulgaris), di formare un cristallino dal suo margine irideo (inRana esculenta): infatti esse proprietà si estrinsecano anche oltre che al di fuori dell'influenze degli organi circostanti al di fuori dell'intero organismo. 相似文献
315.
M Moustafa-Kamal I Gamache Y Lu S Li J G Teodoro 《Cell death and differentiation》2013,20(10):1393-1403
Bcl-2-interacting mediator of cell death (Bim) is a pro-apoptotic B-cell lymphoma 2 family member implicated in numerous apoptotic stimuli. In particular, Bim is required for cell death mediated by antimitotic agents, however, mitotic regulation of Bim remains poorly understood. Here, we show that the major splice variant of Bim, BimEL, is regulated during mitosis by the Aurora A kinase and protein phosphatase 2A (PP2A). We observed that BimEL is phosphorylated by Aurora A early in mitosis and reversed by PP2A after mitotic exit. Aurora A phosphorylation stimulated binding of BimEL to the F-box protein beta-transducin repeat containing E3 ubiquitin protein ligase and promoted ubiquitination and degradation of BimEL. These findings describe a novel mechanism by which the oncogenic kinase Aurora A promotes cell survival during mitosis by downregulating proapoptotic signals. Notably, we observed that knockdown of Bim significantly increased resistance of cells to the Aurora A inhibitor MLN8054. Inhibitors of Aurora A are currently under investigation as cancer chemotherapeutics and our findings suggest that efficacy of this class of drugs may function in part by enhancing apoptotic activity of BimEL. 相似文献
316.
Neera Sriskandarajah Paola Blanchette Thomas J. Kucharski Jose G. Teodoro Philip E. Branton 《Journal of virology》2015,89(8):4685-4689
The adenovirus E4orf4 protein expressed at high levels kills cancer cells but not normal human primary cells. Previous studies suggested that disruption of processes that regulate mitosis may underlie E4orf4 toxicity. Here we have used live imaging to show that E4orf4 induces a slowed defective transit through mitosis, exhibiting a delay or often failure in cytokinesis that may account for an accumulation of G1 tetraploids in the population of dying E4orf4-expressing cells. 相似文献
317.
Darío A. Bianchi Luciano Brambilla Martha A. Gattuso Teodoro S. Kaufman 《Journal of Plant Growth Regulation》2006,25(4):332-338
The synthesis of isochroman derivatives 4–9 from α-hydroxylactone 3 is reported. These heterocycles, carrying different substituents on C-3, C-4, and C-8, exhibited different degrees of inhibition
of the vegetative growth of wheat (Triticum aestivum cv Klein Escorpion) plants, whereas plant developmental patterns such as their protein profile, carotenes/chlorophylls ratio,
and weight/length relationship were not significantly affected. Microscopic observation of transverse sections of shoots and
roots showed morphological changes in the treated plants, consistent with delayed development. The results suggest that among
these isochromans the C-3 carbonyl moiety of the lactone and the C-4 free hydroxyl group are important but not essential for
activity, and that a short side chain appended to C-3 is tolerated. However, cleavage of the C-8 methyl ether group to the
related free phenol causes a drastic reduction in the growth inhibitory activity. 相似文献
318.
Todd K. Jones Charles Pathirana Mark E. Goldman Lawrence G. Hamann Luc J. Farmer Teodoro Ianiro Michael G. Johnson Steven L. Bender Dale E. Mais Robert B. Stein 《The Journal of steroid biochemistry and molecular biology》1996,56(1-6):61-66
Utilizing the co-transfection assay as a guide to determining structure activity relationships, we have been pursuing the discovery of non-steroidal hPR modulators. Small molecule, non-steroidal lead structures have been identified. Optimization of these structures has yielded more potent hPR modulators. Improved cross-reactivity profiles with other intracellular receptors are a feature of these compounds owing to their non-steroidal nature. 相似文献
319.