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961.
Seil M El Ouaaliti M Fontanils U Etxebarria IG Pochet S Dal Moro G Marino A Dehaye JP 《Purinergic signalling》2010,6(4):405-416
The response to ATP of peritoneal macrophages from wild-type (WT) and P2X7-invalidated (KO) mice was tested. Low concentrations (1–100 μM) of ATP transiently increased the intracellular concentration
of calcium ([Ca2+]i) in cells from both mice. The inhibition of the polyphosphoinositide-specific phospholipase C with U73122 inhibited this
response especially in WT mice suggesting that the responses coupled to P2Y receptors were potentiated by the expression of
P2X7 receptors. One millimolar ATP provoked a sustained increase in the [Ca2+]i only in WT mice. The response to 10 μM ATP was potentiated and prolonged by ivermectin in both mice. One millimolar ATP increased
the influx of extracellular calcium, decreased the intracellular concentration of potassium ([K+]i) and stimulated the secretion of interleukin-1β (IL-1β) only in cells from WT mice. Ten micromolar ATP in combination with
3 μM ivermectin reproduced these responses both in WT and KO mice. The secretion of IL-1β was also increased by nigericin
in WT mice and the secretory effect of a combination of ivermectin with ATP in KO mice was suppressed in a medium containing
a high concentration of potassium. In WT mice, 150 μM BzATP stimulated the uptake of YOPRO-1. Incubation of macrophages from
WT and KO mice with 10 μM ATP resulted in a small increase of YOPRO-1 uptake, which was potentiated by addition of 3 μM ivermectin.
The uptake of this dye was unaffected by pannexin-1 blockers. In conclusion, prolonged stimulation of P2X4 receptors by a combination of low concentrations of ATP plus ivermectin produced a sustained activation of the non-selective
cation channel coupled to this receptor. The ensuing variations of the [K+]i triggered the secretion of IL-1β. Pore formation was also triggered by activation of P2X4 receptors. Higher concentrations of ATP elicited similar responses after binding to P2X7 receptors. The expression of the P2X7 receptors was also coupled to a better response to P2Y receptors. 相似文献
962.
Background
In heterogeneous environments, sex-biased dispersal could lead to environmental adaptive parental effects, with offspring selected to perform in the same way as the parent dispersing least, because this parent is more likely to be locally adapted. We investigate this hypothesis by simulating varying levels of sex-biased dispersal in a patchy environment. The relative advantage of a strategy involving pure maternal (or paternal) inheritance is then compared with a strategy involving classical biparental inheritance in plants and in animals. 相似文献963.
Jang-Seu Ki Dae-Sik Hwang Tae-Jin Park Sang-Hoon Han Jae-Seong Lee 《Molecular biology reports》2010,37(4):1943-1955
Otter populations are declining throughout the world and most otter species are considered endangered. Molecular methods are
suitable tools for population genetic research on endangered species. In the present study, we analyzed the complete mitochondrial
genome (mitogenome) sequence of the Eurasian otter Lutra lutra. The mitochondrial DNA sequence of the Eurasian otter is 16,505 bp in length and consists of 13 protein-coding genes, 22
tRNAs, 2 rRNAs, and a control region (CR). The CR sequence of otters from Europe and Asia showed nearly identical numbers
and nucleotide sequences of minisatellites. Phylogenetic analysis of Mustelidae mitogenomes, including individual genes, revealed
that Lutrinae and Mustelinae form a clade, and that L. lutra and Enhydra lutris are sister taxa within the Lutrinae. Phylogenetic analyses revealed that of the 13 mitochondrial protein-coding genes, ND5
is the most reliable marker for analysis of phylogenetic relationships within the Mustelidae. 相似文献
964.
We compared species composition and diversity of the soil seed and seedling banks in three secondary vegetation types (shrubland, Populus bonatii forest, Lithocarpus regrowth forest) and a primary old-growth forest in the subtropical Ailao Mountains of southwestern China to clarify the importance of seed and seedling banks for forest dynamics. The average species richness was the highest in soil samples from the shrubland (26.80 ± 1.98), and the lowest from the primary forest (9.93 ± 0.50). The density of germinable tree seeds increased from the secondary vegetation to the primary forest, and the density of shrub, forb, and graminoid seeds decreased significantly. The most abundant seedlings recorded in soil samples were light-demanding species in the shrubland and Populus bonatii forest. For ground flora, the number of shrub seedlings strongly decreased with the increase in stand age, and shade-tolerant tree seedlings tended to increase. The species similarity between the seed bank and the aboveground vegetation in all sites was low (Sørensen’s index = 0.11–0.33), however, the shrubland had higher similarity compared with the other three plant communities. In the primary forest, light-demanding woody species dominated in soil seed banks, while shade-tolerant species dominated in the overstory and the forest floor. In the primary forest, seedlings of dominant tree species were rare in the understory, and no seeds of the dominant species were found in the soil. Results indicated that the early stages of vegetation recovery should take into account the possibility of recovering soil seed bank processes. However, colonization and establishment of tree seedlings will be difficult once a primary forest is destroyed. 相似文献
965.
Andrzej Bunio Renata Szygula Slawomir Tubek Grzegorz Krasowski 《Biological trace element research》2010,136(2):149-156
Environmental factors significantly influence the incidence and course of metabolic syndrome diseases such as diabetes and
obesity. The content of elements in rainwater is an indirect indicator of their presence in dust suspended in the air. In
this paper we present the relationships between the content of selected elements in rainwater and hospitalization frequencies
due to diabetes (E10–E13) and obesity (E66). It was assumed that the hospitalization frequency could be taken as a measure
of deterioration of the metabolic process in the course of diabetes and its complications. The observations concerned the
population of Opole Voivodeship, Poland (one million inhabitants), distributed in small communities of 44,000 to 151,000 inhabitants
during the years 2000–2002. In cases of diabetes E10–E13 for all subjects relevant correlation indicators were found for chromium
(r = 0.71), cadmium (r = 0.65), and lead (r = 0.66). Borderline relevance was seen for copper (r = 0.57) and zinc (r = 056). For diabetic men the statistically relevant correlations were chromium (r = 0.79), lead (r = 0.77), cadmium (r = 0.74), copper (r = 0.70), chloride (r = 0.69), zinc (r = 0.68), and iron (r = 0.64). For women the only relevant correlations were chromium (r = 0.62) and cadmium (r = 0.55). No significant correlations were found in obese individuals of both sexes. 相似文献
966.
Photoperiodic inhibition of potato tuberization: an update 总被引:1,自引:0,他引:1
Debabrata Sarkar 《Plant Growth Regulation》2010,62(2):117-125
967.
Xiaoping Wu Jisen Shi Mengli Xi Zewei Luo Xiaohua Hu 《Plant Molecular Biology Reporter》2010,28(4):684-691
The classical ABC model proposed for flower development in Arabidopsis and Antirrhinum appropriately sheds light on the biological process of flower development and differentiation and serves in manipulating
the floral structure of other important ornamental plants. In this study, LLGLO1, a B functional gene from Lilium longiflorum was isolated and characterized. RT-PCR analysis elucidated that temporal and spatial expression pattern of LLGLO1. This putative gene was strongly expressed in 1, 2, and 3 whorl organs, i.e., outer whorl tepals, inner whorl tepals, and
stamens. Genetic effect of LLGLO1 was assayed by ectopic expression in model plant Arabidopsis. Transformed plants showed homeotic transformation of sepals into petaloid sepals in the first whorl, which is similar to
the transgenic plants of 35S::PI. So LLGLO1 was one member of GLO/PI sub-family gene to function in flower development. 相似文献
968.
Background
Chow and Liu showed that the maximum likelihood tree for multivariate discrete distributions may be found using a maximum weight spanning tree algorithm, for example Kruskal's algorithm. The efficiency of the algorithm makes it tractable for high-dimensional problems. 相似文献969.
ARTEMIS stabilizes the genome and modulates proliferative responses in multipotent mesenchymal cells
Background
Unrepaired DNA double-stranded breaks (DSBs) cause chromosomal rearrangements, loss of genetic information, neoplastic transformation or cell death. The nonhomologous end joining (NHEJ) pathway, catalyzing sequence-independent direct rejoining of DSBs, is a crucial mechanism for repairing both stochastically occurring and developmentally programmed DSBs. In lymphocytes, NHEJ is critical for both development and genome stability. NHEJ defects lead to severe combined immunodeficiency (SCID) and lymphoid cancer predisposition in both mice and humans. While NHEJ has been thoroughly investigated in lymphocytes, the importance of NHEJ in other cell types, especially with regard to tumor suppression, is less well documented. We previously reported evidence that the NHEJ pathway functions to suppress a range of nonlymphoid tumor types, including various classes of sarcomas, by unknown mechanisms. 相似文献970.