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151.
BACKGROUND: PPARdelta (NR1C2) promotes lipid accumulation in human macrophages in vitro and has been implicated in the response of macrophages to vLDL. We have investigated the role of PPARdelta in PMA-stimulated macrophage differentiation.The THP-1 monocytic cell line which displays macrophage like differentiation in response to phorbol esters was used as a model system. We manipulated the response to PMA using a potent synthetic agonist of PPARdelta, compound F. THP-1 sub-lines that either over-expressed PPARdelta protein, or expressed PPARdelta anti-sense RNA were generated. We then explored the effects of these genetic modulations on the differentiation process. RESULTS: The PPARdelta agonist, compound F, stimulated differentiation in the presence of sub-nanomolar concentrations of phorbol ester. Several markers of differentiation were induced by compound F in a synergistic fashion with phorbol ester, including CD68 and IL8. Over-expression of PPARdelta also sensitised THP-1 cells to phorbol ester and correspondingly, inhibition of PPARdelta by anti-sense RNA completely abolished this response. CONCLUSIONS: These data collectively demonstrate that PPARdelta plays a fundamental role in mediating a subset of cellular effects of phorbol ester and supports observations from mouse knockout models that PPARdelta is involved in macrophage-mediated inflammatory responses. 相似文献
152.
K. V. Efimova M. A. Kreshchenovskaya N. A. Aizdaicher T. Yu. Orlova 《Russian Journal of Marine Biology》2014,40(5):364-374
In this paper, we present the results of a comparative genetic and ultrastructural study of three clones of the microalga Porphyridium purpureum (Rhodophyta) from the culture collection of marine microalgae of the Zhirmunsky Institute of Marine Biology. All clones, which have different geographical origins, showed a high similarity in terms of the ultramicroscopic structure and the nucleotide sequences of the nuclear ribosomal DNA genes (18S rDNA, ITS1-5.8S rDNA-ITS2, D1-D2 region of 28S rDNA). The obtained data are very helpful for the certification of two strains of P. purpureum that were isolated for the first time in the practice of Russian algological research. 相似文献
153.
E. M. MIEDZIEJKO G. B. PLENZLER D. M. NAPIERAA A. T. NARONA 《Plant, cell & environment》1996,19(12):1443-1448
The 1H-NMR spin-spin relaxation time (T2) in Triticale seeds swelling in external osmotica, polyethylene glycol 8000 or mannitol can identify both bound and free water. At the same water content, the free water spin-spin relaxation time increases for seeds imbibed with the mannitol solution, demonstrating inadequate water potential adjustment. The exchange rate of free/bound water molecules is apparently influenced by the driving force for water flow. The reciprocal lifetime of free water molecules, as a measure of water flow through the main cell barrier, was obtained. From a model of the seed as a resistance–capacitor network for water flow, a method was derived for calculating the reflection coefficient σ as a lifetime ratio of the free water molecules in seeds imbibed with two different osmotica (one penetrating across the main cell barrier and one not penetrating) at the same water potential. The 1H-NMR method and the classical method based on volume rate changes yielded reflection coefficients for mannitol for the cell wall–plasmalemma barrier of 0.78 ± 0.08 and 0.68 ± 0.06, respectively. 相似文献
154.
经对猪蛔虫雌虫体长,体重,子宫瞬间怀卵总量,相对毓力测定,发现怀卵总量与体长,体重有密切关系,呈正相关,还发现相对繁殖力,以体重1.01-3.00g,范围最佳,繁殖能力最强。 相似文献
155.
小叶臭黄皮叶挥发油化学成分的研究 总被引:8,自引:0,他引:8
采用水蒸气蒸馏法提取小叶臭黄皮叶挥发油,运用毛细管气相色谱-质谱联用法对挥发油成分进行了分析,共分离出84个峰,鉴定了其中的66种成分,所鉴定成分占挥发油总量的94.52%.其主要化学成分为α-芹子烯(15.76%)、石竹烯(15.05%)、β-芹子烯(9.54%)、α-蒎烯(6.43%)和α-石竹烯(5.39%)等. 相似文献
156.
MAI Tiejun* WANG Xin* ZHANG Zhiwen XIN Dianqi NA Yanqun & GUO Yinglu . Institute of Urology First Hospital of Peking University Beijing China . Department of General Surgery First Hospital of Peking University Beijing China . Department of Physiology Peking University Beijing China 《中国科学:生命科学英文版》2004,(5)
157.
158.
Evolutionary rates for tuf genes in endosymbionts of aphids 总被引:4,自引:1,他引:4
The gene encoding elongation factor Tu (tuf) in aphid endosymbionts (genus
Buchnera) evolves at rates of 1.3 x 10(-10) to 2.5 x 10(-10) nonsynonymous
substitutions and 3.9 x 10(-9) to 8.0 x 10(-9) synonymous substitutions per
position per year. These rates, which are at present among the most
reliable substitution rates for protein-coding genes of bacteria, have been
obtained by calibrating the nodes in the phylogenetic tree produced from
the Buchnera EF-Tu sequences using divergence times for the corresponding
ancestral aphid hosts. We also present data suggesting that the rates of
nonsynonymous substitutions are significantly higher in the endosymbiont
lineages than in the closely related free-living bacteria Escherichia coli
and Salmonella typhimurium. Synonymous substitution rates for Buchnera
approximate estimated mutation rates for E. coli and S. typhimurium, as
expected if synonymous changes act as neutral mutations in Buchnera. We
relate the observed differences in substitution frequencies to the absence
of selective codon preferences in Buchnera and to the influence of Muller's
ratchet on small asexual populations.
相似文献
159.