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81.
Chemokine-like factor 1 (CKLF1) is a cytokine with chemotactic effects on leukocytes and a functional ligand of CCR4. This cytokine is widely expressed and the level of expression is reported to be upregulated in asthma and rheumatoid arthritis (RA), disease conditions in which T lymphocytes are over-activated. In order to determine the expression profile of CKLF1 in activated T lymphocytes, we first employed a PCR-based method on human blood fractions cDNA panels and found that CKLF1 was upregulated in activated CD4+ and CD8+ cells, with no obvious changes in CD19+ cells. We further performed kinetic analyses of CKLF1 expression in phytohemagglutinin (PHA)-stimulated human peripheral blood lymphocytes (PBL) at both the mRNA and protein levels. In resting PBL, the constitutive expression of CKLF1 was low at mRNA level and barely detectable at the protein level; however, both were remarkably upregulated by PHA, appearing at 8h after PHA-stimulation and persisting up to 72h. These results suggest that CKLF1 may be involved in T lymphocyte activation and further study of CKLF1 function will prove valuable. 相似文献
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探讨模拟冷空气降温过程对健康大鼠和高血压大鼠凝血功能的影响 总被引:1,自引:0,他引:1
目的:通过模拟冷空气温度变化过程给予健康大鼠和高血压大鼠冷刺激,以此探讨冷空气过程对机体凝血功能的影响。方法:收集张掖市2011年3月一次典型冷空气过程数据,利用气象环境模拟箱模拟其温度变化过程。将24只雄性健康大鼠和24只雄性高血压大鼠分别随机分成最低温组(Tmin组)、Tmin对照组、复温组(Tr组)和Tr对照组。将Tmin组和Tr组大鼠放入气候箱中暴露冷空气温度变化过程。在Tmin和Tr时点分别停止Tmin组大鼠和Tr组大鼠冷空气暴露,并采血以测定其凝血功能指标—凝血四项。结果:与对照组相比,健康大鼠和高血压大鼠活化部分凝血酶原时间(APTT)、凝血酶原时间(PT)、凝血酶时间(TT)在降温后与对照组相比没有显著差异(P>0.05),但血浆纤维蛋白原(Fbg)含量在高血压大鼠和健康大鼠Tmin组明显高于其对照组(P<0.01)。温度恢复后,其在健康组含量仍然高于其对照组(P<0.05),而在高血压大鼠中没有差异(P>0.05)。同Fbg,反应Fbg的纤维蛋白原时间(Fbg-time)在健康大鼠Tmin和Tr组中短于对照组(P<0.01,),而在高血压大鼠中仅在Tmin组短于对照组(P<0.01)。高血压大鼠血中的Fbg含量和Fbgt明显高于和短于健康大鼠(P<0.01)。结论:①冷空气降温过程能增加机体血中Fbg含量,使凝血功能增强,可能增加心血管疾病危险性;②冷空气刺激对健康大鼠凝血功能影响强于高血压大鼠。 相似文献
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Songwen Lin Chunyang Wang Ming Ji Deyu Wu Yuanhao Lv Li Sheng Fangbin Han Yi Dong Kehui Zhang Yakun Yang Yan Li Xiaoguang Chen Heng Xu 《Bioorganic & medicinal chemistry》2018,26(3):637-646
A series of new thienopyrimidine derivatives has been discovered as potent PI3K inhibitors. The systematic SAR studies for these analogues are described. Among them, 8a and 9a exhibit nanomolar enzymatic potencies and sub-micromolar cellular anti-proliferative activities. 8a displays favorable pharmacokinetic profiles, while 9a easily undergoes deacetylation to yield a major metabolite 8a. Furthermore, 8a and 9a potently inhibit tumor growth in a dose-dependent manner in the NCI-H460 xenograft model with an acceptable safety profile. 相似文献
87.
Alzheimer’s disease (AD) is characterized by an excessive accumulation of toxic amyloid beta (Aβ) plaques and memory dysfunction. The onset of AD is influenced by age, genetic background, and impaired glucose metabolism in the brain. Several studies have demonstrated that diabetes involving insulin resistance and glucose tolerance could lead to AD, ultimately resulting in cognitive dysfunction. Even though the relationship between diabetes and AD was indicated by significant evidences, the critical mechanisms and metabolic alterations in diabetes induced AD are not clear until now. Recently, iron metabolism has been shown to play multiple roles in the central nervous system (CNS). Iron deficiency and overload are associated with neurodegenerative diseases. Iron binds to Aβ and subsequently regulates Aβ toxicity in the CNS. In addition, previous studies have shown that iron is involved in the aggravation of insulin resistance. Considering these effects of iron metabolism in CNS, we expect that iron metabolism may play crucial roles in diabetic AD brain. Thus, we review the recent evidence regarding the relationship between diabetes-induced AD and iron metabolism. 相似文献
88.
Duplication and adaptive evolution of the chalcone synthase genes of Dendranthema (Asteraceae) 总被引:10,自引:0,他引:10
Chalcone synthase (CHS) is a key enzyme in the biosynthesis of flavonoids, which are important for the pigmentation of flowers and act as attractants to the pollinators. Genes encoding CHS constitute a multigene family in which the copy number varies among plant species and functional divergence appears to have occurred repeatedly. Plants of the Dendranthema genus have white, yellow, and pink flowers, exhibiting considerable variation in flower color. In this article, 18 CHS genes from six Dendranthema species were sequenced. Two of them were found to be pseudogenes. The functional Dendranthema CHS genes formed three well-supported subfamilies: SF1, SF2, and SF3. The inferred phylogeny of the CHS genes of Dendranthema and Gerbera suggests that those genes originated as a result of duplications before divergence of these two genera, and the function of Dendranthema CHS genes have diverged in a similar fashion to the Gerbera CHS genes; i.e., the genes of SF1 and SF3 code for typical CHS enzymes expressed during different stages of development, whereas the genes of SF2 code for another enzyme that is different from CHS in substrate specificity and reaction. Relative rate tests revealed that the Dendranthema CHS genes significantly deviated from clocklike evolution at nonsynonymous sites. Maximum likelihood analysis showed that the nonsynonymous-synonymous (omega = d(N)/d(S)) rate ratio for the lineage ancestral to SF2 was much higher than for other lineages, with some sites having a ratio well above one. Positive selective pressure appears to have driven the divergence of SF2 from SF1 and SF3. 相似文献
89.
Zhang Hao Wang Jin-Yan Chen Yi-Juan Siemann Evan Ji Xiang-Yun Jiang Jie-Xian Wan Nian-Feng 《BioControl》2022,67(1):1-13
BioControl - The effects of plant volatiles on parasitoids are important with regards to the tri-trophic interactions among host plants, insect herbivores, and their natural enemies. However, the... 相似文献
90.
Chuncheng Lu Miaofei Xu Ying Wang Yufeng Qin Guizhen Du Wei Wu Xiumei Han Chao Ji Yanli Yang Aihua Gu Yankai Xia Ling Song Shoulin Wang Xinru Wang 《PloS one》2013,8(1)