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61.
Hydraulic architecture and water relations of Spartium junceum branches affected by a mycoplasm disease 总被引:1,自引:0,他引:1
Plant water relations, xylem anatomy and the hydraulic architecture of 1‐year‐old twigs of Spartium junceum, both healthy and affected by a phytoplasm disease, were studied. The disease causes twigs to be either shortened (witches broom disease, WBD) or flat (fasciate disease, FD). WBD twigs show a sevenfold increase in total leaf area, smaller and shorter xylem conduits, a higher stomatal conductance (gl) and a decline of minimum leaf water potentials ( Ψ l) below the turgor loss point. FD twigs had nearly twice the leaf area of the healthy controls as well as high gl values and Ψ l values below the turgor loss point. Moreover, significant differences between healthy and affected twigs in stem stomatal conductance (gs) and in the total stem area were recorded. Affected twigs die back under drought stress, which is explained by a pronounced loss of hydraulic conductivity of the infected stems (40 and 60%) in FD and WBD as well as by the unfavourable ratio of weighted conduit radius ( Σ r4) to total surface area (At), so that the efficiency of the stem in supplying the whole transpiring area with water is strongly reduced. 相似文献
62.
Su Jing Chan Chou Chai Tze Wei Lim Mie Yamamoto Eng H Lo Mitchell Kim Peng Lai Peter Tsun Hon Wong 《ASN neuro》2015,7(2)
Hydrogen sulfide (H2S) has been reported to exacerbate stroke outcome in experimental models. Cystathionine β-synthase (CBS) has been implicated as the predominant H2S-producing enzyme in central nervous system. When SH-SY5Y cells were transfected to overexpress CBS, these cells were able to synthesize H2S when exposed to high levels of enzyme substrates but not substrate concentrations that may reflect normal physiological conditions. At the same time, these cells demonstrated exacerbated cell death when subjected to oxygen and glucose deprivation (OGD) together with high substrate concentrations, indicating that H2S production has a detrimental effect on cell survival. This effect could be abolished by CBS inhibition. The same effect was observed with primary astrocytes exposed to OGD and high substrates or sodium hydrosulfide. In addition, CBS was upregulated and activated by truncation in primary astrocytes subjected to OGD. When rats were subjected to permanent middle cerebral artery occlusion, CBS activation was also observed. These results imply that in acute ischemic conditions, CBS is upregulated and activated by truncation causing an increased production of H2S, which exacerbate the ischemic injuries. Therefore, CBS inhibition may be a viable approach to stroke treatment. 相似文献
63.
64.
Here mitochondrial morphology and dynamics were investigated in Medicago truncatula cell-suspension cultures during growth and senescence. Cell biology techniques were used to measure cell growth and death in culture. Mitochondrial morphology was investigated in vivo using a membrane potential sensor probe coupled with confocal microscopy. Expression of a senescence-associated gene (MtSAG) was evaluated in different cell-growth phases. Mitochondria appeared as numerous, punctuate organelles in cells at the beginning of the subculture cycle, while interconnected networks were observed in actively growing cells. In senescent cells, giant mitochondria were associated with dying cells. The release of cytochrome c from mitochondria was detected in different growth phases of cultured cells. Studies on plant cell cultures allowed us to identify physiological and molecular markers of senescence and cell death, and to associate distinct mitochondrial morphology with cells under different physiological conditions. 相似文献
65.
Individual mouse strains differ significantly in terms of behavior and cognitive function. Strain-specific variation of metabolic
protein levels in the hippocampus among various commonly used mouse strains, however, has not been investigated yet. A proteomic
approach based on two-dimensional gel electrophoresis (2-DE) coupled with mass spectrometry [high capacity ion trap (HCT)]
has been chosen to address this question by determining strain-dependent levels of metabolic proteins in hippocampal tissue
of four inbred and one outbred mouse strain. Statistical analysis of protein spots on 2-DE gels of the individual strains
(n = 10) revealed significant strain-dependent differences in densities of 39 spots. Subsequent HCT analysis led to the identification
of 22 different metabolic proteins presenting with differential protein levels among the five mouse strains investigated.
Among those are proteins concerned with the metabolism of amino acid, nucleic acid, carbohydrate and energy. Moreover, proteins
known to play a pivotal role in the processes of learning and memory, such as calcium/calmodulin-dependent protein kinase type II alpha chain, were found to present with significant inter-strain variability, which is also in agreement with our previous reports. Strain-specific
protein levels of metabolic proteins in the mouse hippocampus may provide some insight into the molecular underpinnings and
genetic determination of strain-dependent neuronal function. Furthermore, data presented herein emphasize the significance
of the genetic background for the analysis of metabolic pathways in the hippocampus in wild-type mice as well as in gene-targeting
experiments. 相似文献
66.
Thomas Troxler Paulette Greenidge Kaspar Zimmermann Sandrine Desrayaud Peter Drückes Tatjana Schweizer Daniela Stauffer Giorgio Rovelli Derya R. Shimshek 《Bioorganic & medicinal chemistry letters》2013,23(14):4085-4090
Mutations in leucine-rich repeat kinase-2 (LRRK2) are the most common genetic cause of Parkinson’s disease (PD). The most frequent kinase-enhancing mutation is the G2019S residing in the kinase activation domain. This opens up a promising therapeutic avenue for drug discovery targeting the kinase activity of LRRK2 in PD. Several LRRK2 inhibitors have been reported to date. Here, we report a selective, brain penetrant LRRK2 inhibitor and demonstrate by a competition pulldown assay in vivo target engagement in mice. 相似文献
67.
The effect of high alkaline pH on the reinitiation of cell growth was studied in six different mammalian cells. We failed to confirm the observation of Zetterberg & Engström, Proc natl acad sci US 78 (1981) 4334 [17] and Exp cell res 144 (1983) 199 [18]. Treatment of quiescent cells at pH 9.5 did not stimulate cell growth when measured by total protein/flask or increase in cell number. 相似文献
68.
Molecular characterization of a cystathionine beta-synthase gene,CBS1, in Magnaporthe grisea 总被引:1,自引:0,他引:1 下载免费PDF全文
CBS1 from Magnaporthe grisea is a structural and functional homolog of the cystathionine β-synthase (CBS) gene from Saccharomyces cerevisiae. Our studies indicated that M. grisea can utilize homocysteine and methionine through a CBS-independent pathway. The results also revealed responses of M. grisea to homocysteine that are reminiscent of human homocystinuria. 相似文献
69.
Jean-François Fournier Yushma Bhurruth-Alcor Branislav Musicki Jérome Aubert Michèle Aurelly Claire Bouix-Peter Karinne Bouquet Laurent Chantalat Marion Delorme Bénédicte Drean Gwenaelle Duvert Nicolas Fleury-Bregeot Blanche Gauthier Karine Grisendi Craig S. Harris Laurent F. Hennequin Tatiana Isabet Florence Joly Loïc Tomas 《Bioorganic & medicinal chemistry letters》2018,28(17):2985-2992
A series of squaramide-based hydroxamic acids were designed, synthesized and evaluated against human HDAC enzyme. Squaramides were found to be potent in the Hut78 cell line, but initially suffered from low solubility. Leads with improved solubility and metabolic profiles were shown to be class I, IIB and IV selective. 相似文献
70.